
C.T. Dearing Prinfmcj Co, 



PHYSIOLOGY 
HYGIENE and 
SANITATION 



An Elementary Text-Book of Physiology, with special attention 
given to Hygiene and Sanitation 

BY 

W. L. HEIZER, M. D. 

One time State Registrar of Vital Statistics lor Kentucky; Executive Secretary Kentucky Board ol 

Tuberculosis Commissioners; Executive Secretary of the Reorganized State Board of 

Health of Kentucky; now Executive Secretary Kentucky State Health 

and Welfare League. 



19 19 



C. T. Dearing Printing Co,, Incorporated 

Louisville, Ky. 






Copyright 1919 by 

C. T. Dearing Printing Company 

Incorporated 



APR -2 1919 

©CLA515006 



INTRODUCTION 



In the preparation of this book, one central idea pre- 
vails throughout — that of application of such knowledge 
to the life of the individual and the community that 
health may be preserved. Enough physiology is given 
in its relation to gross and minute anatomy to make clear 
the laws of health and the necessity for obeying them. 

The writer realizes that it will be a long time before 
we shall cease to have opportunities to become infected 
with diseases that will be spread by careless, indifferent 
or ignorant people, but the effort is made in this book to 
create a health conscience so that when a communicable 
disease attacks an individual who knows how such dis- 
eases are spread, he will feel morally bound to try to limit 
it to his own household. When the public is educated to 
this degree, the spread of such diseases will be prevented 
to a large extent. 

No apology is made for a frank discussion of the dis- 
eases caused solely by the carelessness in disposing of 
body wastes. A large number of people are dying each 
year of typhoid fever, dysentery (flux) and "summer 
complaint" (diarrhoea and enteritis) in children, every 
school district in the state being represented. These and 
many thousands more of our citizens are being made ser- 
iously ill because we have been too modest to tell our 
children that these body wastes are poisons. 

The necessity for an efficient local and state board of 
health is made plain so that, with proper sentiment de- 
manding it, the state and local laws for the protection of 
the people may be enforced. 

3 



4 INTRODUCTION 

Why do we need a practical, health and life-saving phy- 
siology? The records of death on file in the Bureau of 
Vital Statistics of the State Boards of Health show that 
of the deaths registered nearly one-half are due to dis- 
eases that are practically preventable. 

There are today in every state thousands of people, 
who recently attended our public schools, who do not 
know that tuberculosis, typhoid fever, diphtheria, and 
many other diseases come from seed (germs) and that to 
prevent these dreaded diseases, one has only to prevent 
these seed from being scattered and grown in other peo- 
ple. 

As a result of this lack of information about one of 
every seven funerals that occur is caused from tubercu- 
losis (consumption) and thousands who are ill of it are 
scattering the seed in every community so that about 
one of every seven of the children, for whom the state is 
now spending millions of dollars to educate, will die of 
this disease, and nearly one-half of them will die in the 
prime of their lives of diseases which are practically pre- 
ventable, unless they are taught the means of saving 
themselves. 

Many thousands of our people shorten their lives and 
become less efficient by the use of tobacco and alcohol; 
through ignorance of the value of pure food, water and 
air, and as a result of immorality. The school physio- 
logy is not complete if it does not arm the individual with 
the knowledge and purpose to avoid these errors and 
enable him to live in harmony with the laws of health. 

The people spend foolishly a vast sum of money for 
patent medicines, many of them containing poison and 
alcohol, which usually do not do any good and may do 
a great deal of harm by the formation of a "drug habit' ' 



INTRODUCTION 5 

or by delaying the proper treatment of a disease until 
all hope for cure is lost. 

The average state pays to her dentists each year hun- 
dreds of thousands of dollars for constructing and re- 
pairing teeth. With the kind of knowledge that compels 
one to keep the mouth and teeth clean, and in the absence 
of disease, no one need pay a dentist much for repair, ex- 
cept as a result of an accident, or need suffer any of the 
terrible pain of neglected teeth. 

From these considerations, it is evident that we must 
teach the children of today, what we, yesterday, did not 
know about the causes and prevention of disease that, 
tomorrow, the people may live longer, happier, freer 
from sickness and be able to carry on the warfare against 
disease with less opposition from ignorant people who 
must be protected in spite of themselves. 



TABLE OF CONTENTS 



ILLUSTRATIONS (153) 

INTRODUCTION. 

Chapter. Page 

I. THE HUMAN BODY A MACHINE 17 

II. THE SYSTEMS OF THE BODY 21 

a. Gross Anatomy. 

b. Organs. 

c. Sickness. 

III. BODY CELLS 25 

a. Minute Anatomy. 

b. Cell Enemies. 

IV. CELL ENEMIES 30 

a. Bacteria. 

b. Helpful Bacteria. 

c. Harmless Bacteria. 

d. Harmful Bacteria. 

e. Shapes of Bacteria. 

V. BACTERIA 35 

a. How to Grow Bacteria. 

b. Food for Germs. 

c. Warmth for Germs. 

d. Absence of Sunlight. 

e. How Disease Germs Spread. 

f. How Germs are Killed. 

VI. THE OSSEOUS SYSTEM— THE SKELETON.... 42 

a. Uses of the Bones. 

b. Kinds of Bones as to Shape. 

c. Joints. 

d. Structure of Bones. 

7 



8 TABLE OF CONTENTS 

Chapter Page 
VII. HYGIENE OF THE OSSEOUS SYSTEM 51 

a. Care of the Bones. 

b. Dislocations. 

c. Sprains. 

d. Fractures. 

e. Stooped Shoulders. 

f. Bone Felons. 

g. Other Bone Diseases Caused by Germs, 
h. White Swelling. 

i. Pott's Disease. 

VIII. THE MUSCULAR SYSTEM 57 

a. Power of Locomotion. 

b. Connective Tissue. 

c. The Muscles and Their Function. 

d. Muscular Sense. 

e. Attachment of Muscles. 

f. Arrangement of Muscles. 

g. Training of Muscles. 

h. Muscle Wear and Repair. 

IX. HYGIENE OF THE MUSCULAR SYSTEM 68 

a. Exercise. 

b. Form of Exercise. 

c. Exercise of Occupation. 

d. Games. 

e. When to Exercise. 

f. Muscle Enemies. 

g. Tobacco and Alcohol, 
h. An Erect Figure. 

X. THE DIGESTIVE SYSTEM 74 

a. Chemistry. 

b. Composition of Matter. 

c. Composition of Vegetable and Animal Matter. 

d. Life by Death. 



TABLE OF CONTENTS 



Chapter 






XL 


THE 


ORGANS OF DIGESTION. 




a. 


Mastication. 




b. 


Insalivation. 




c. 


Gastric Digestion. 




d. 


Intestinal Digestion. 




e. 


Absorption. 




f. 


Assimilation. 



Page 
.. 80 



XII. KINDS AND QUANTITIES OF FOODS., 
a. Classes of Food. 



b. 


Water. 


c. 


The Carbo-Hydrates. 


d. 


Fats. 


e. 


Proteids. 


f. 


Minerals. 


g. 


Mixed Foods. 


h. 


Milk. 


i. 


Preparation of Foods. 


J. 


Methods of Cooking. 


k. 


Serving Foods. 


FOODS . 


a. 


Food Values. 


b. 


Table of Food Values. 


c. 


Alcohol. 


d. 


How to Eat. 


e. 


Loss of Appetite. 



XIII. FOODS 96 



XIV. PRESERVATION OF FOODS 103 

a. Refrigeration. 

b. Pickling. 

c. Dehydration. 

d. Dangers of Food. 

XV. MILK ,,,, 1Q9 

a. Care of Milk. 

b. Market Milk, "Certified Milk." 

c. Skimmed Milk. 

d. Butter and Cheese. 



10 



TABLE OF CONTENTS 



Chapter. 
XVI. 



XVII. 



XVIII. 



XIX. 



XX. 



XXI. 



WATER ........ 

a. Water Supplies. 
Polluted Water. 
Examination of Water. 
Purification of Water. 
The Common Drinking Cup. 
Drinking Fountains. 

THE TEETH 

a. Structure of Teeth. 
The Shape of Teeth. 
Injury of Teeth. 
Care of Teeth. 
Repair of Teeth. 

CIRCULATORY SYSTEM 

Blood. 
The Heart. 

The Work of the Heart. 
The Arteries. 
Structure of Arteries. 
The Capillaries. 
Veins. 

The Lymphatics. 
Lymph Glands. 
BLOOD CELLS 

a. Red Blood Cells. 

b. White Blood Cells. 

c. Malaria. 

HYGIENE OF THE CIRCULATION., 
a. Exercise. 

Fresh Air. 

Drugs for Headache. 

Alcohol. 

Tobacco. 
THE RESPIRATORY SYSTEM 

a. Objects of Respiration. 

b. Organs of Respiration. 

c. The Trachea. 



Page 
... 115 



b. 
c. 
d. 
e. 
f. 



b. 
c. 
d. 
e. 

THE 
a. 
b. 
c. 
d. 
e. 
f. 

g. 
h. 
i. 



125 



136 



150 



158 



b. 
c. 
d. 
e. 



163 



TABLE OP CONTENTS 



11 



Chapter. 
XXII. 



XXIII. 



XXIV. 



XXV. 



XXVI. 



XXVII. 



THE 

a. 

b. 

c. 
AIR 

a. 

b. 

c. 
' d. 

e. 

f. 



b. 
c. 
d. 
e. 



Page 

LUNGS 169 

How We Breathe. * 

The Capacity of the Lungs. 

The Rate of Breathing. 
175 

Composition of Air. 

Air Pressure. 

Nitrogen. 

Carbon Dioxide. 

Changes in Expired Air. 

Effect of Breathing Air with Insufficient 

Oxygen. 

VENTILATION 180 

a. Quantity of Air Needed. 

Methods of Ventilation. 

Schoolroom Ventilation, 

Sleeping Room Ventilation. 

Sleeping Porches. 
HYGIENE OF THE RESPIRATORY SYSTEM.... 188 
a. Dust in the Air. 

Gases in the Air. 

Exercise and Air. 

Tight Clothing. 

Postures. 

Alcohol. 

Tobacco. 

INFLUENZA AND "COLDS" 195 

a. Germs in the Air. 

b. Influenza. 

c. Prevention of Influenza. 
TUBERCULOSIS 201 

a. Frequency of Tuberculosis. 
Site of the Disease. 
The Cause of Tuberculosis. 
The Signs or Symptoms of Tuberculosis. 
Examination by Physicians. 
Heredity of "Consumption." 
How the Disease Spreads. 



b. 
c. 
d. 
e. 
f. 
g. 



b. 
c. 
d. 
e. 
f. 
g. 



12 



TABLE OF CONTENTS 



Chapter 
XXVIII. 



XXIX. 



XXX. 



XXXI. 



XXXII. 



XXXIII. 



b. 
c. 
d. 
e. 



Page 
TUBERCULOSIS (Continued 214 

a. Prevention of Tuberculosis. 

b. Treatment of Tuberculosis. 

THE EXCRETORY SYSTEM 220 

a. The Organs of the Excretory System. 

The Kidneys. 

Hygiene. 

Bright's Disease. 

The Bowels. 
THE BODY WASTES IN DISEASE 226 

a. Typhoid Fever. 

b. How the Disease is Spread. 

c. The Prevention of Typhoid Fever. 

BODY WASTES (Continued) 232 

a. Hookworm Disease. 

Cause of Hookworm Disease. 

How the Disease Spreads. 

The Cure of Hookworm Disease. 

Benefits of Treatment. 

Prevention. 

THE SKIN 237 

a. Functions of the Sikn. 

Structure of the Skin. 

Complexions. 

The Dermis. 

The Sweat Glands. 

Heat Regulations of the Body. 

Sickness and Body Temperature. 

HYGIENE OF THE SKIN 244 

a. Bathing. 

Cold Baths. 

The Face and Hands. 

The Feet. 

Clothing. 

Change of Clothing. 

Tight-Fitting Clothing. 

Shoes. 

Flat Feet. 



b. 
c. 
d. 
e. 
f. 



b. 
c. 
d. 
e. 
f. 
g. 



b. 
c. 
d. 
e. 
f. 

g. 
h. 
i. 



TABLE OF CONTENTS 



13 



Chapter Page 

XXXIV. THE NERVOUS SYSTEM 252 

a. The Brain, the Spinal Cord and the Nerves. 

b. How the Nervous System Works. 



XXXV. THE ORGANS OF THE NERVOUS SYSTEM. 

a. The Brain. 

b. The Spinal Cord. 

c. Nerve Cells. 

d. The Nerves. 

e. Plexus of the Nerves. 

f. The Sympathetic Nervous System. 



258 



XXXVI. REFLEX ACTIONS AND HABITS ... 
a. Reflex Action and Character. 



268 



XXXVII. HYGIENE OF THE NERVOUS SYSTEM, 
a. Rest and Sleep. 



273 



b. 
c. 



Tobacco. 
Alcohol. 



XXXVIII. THE SPECIAL SENSES 

a. The Sense of Feeling. 

b. Pain. 

c. Taste. 

d. Smell. 

e. Uses of Smell. 

f. Care of Nose. 



278 



XXXIX. HEARING 

a. Organ of Hearing. 

b. The Outer Ear. 

c. The Middle Ear. 

d. The Internal Ear. 

e. How We Hear. 

f. Care of Ear. 



283 



14 



TABLE OF CONTENTS 



Chapter 






XL. 


SEEINC 




a. 


The Eye Lids. 




b. 


The Eye. 




c. 


How We See. 




d. 


Near Sightedness. 




e. 


Far Sightedness. 




f. 


Astigmatism. 




g. 


A Cataract. 




h. 


Care of the Eyes. 




i. 


Eye Strain. 




J. 


Cross Eyes. 



Page 

.. 290 



XLI. EMERGENCIES 301 

a. Injury by Violence. 

b. Punctures. 

c. Bruises. 

d. Bites of Animals and Stings of Insects. 

e. Burns and Cold. 

f. Frost Bites. 

g. Electric Currents, 
h. Sun Stroke. 

i. Heat Prostration. 



XLII. EMERGENCIES (Continued) 

a. Fainting. 

b. Fits. 

c. Asphyxiation. 

d. Poisons. 

e. Alcohol. 



308 



XLIII. COMMON DISEASES OF CHILDHOOD 

a. General Considerations. 

b. Diphtheria. 

c. Scarlet Fever. 

d. Whooping Cough. 

e. Infantile Paralysis. 

f. Chicken Pox. 

g. Disease Infection, 
h. Chemicals. 



312 



TABLE OP CONTENTS 15 



Chapter 






Page 


XLIV. 


SANI' 
a. 


rATION 


318 




Sanitation of the Home. 






b. 


Garbage. 






c. 


Sanitation of the Community. 






d. 


Health Boards. 






e. 


The State Board of Health. 






f. 


Volunteer Organizations. 






g. 


Tuberculosis Sanatoria. 





CHAPTER I 

THE HUMAN BODY A MACHINE 

A practical knowledge of any machine results from 
a study of its use; its structure, or of the various parts 
composing it; its motive force, or power to make it 
work; its operation, or the way to make it work; the 
care of it, to keep it useful, and the repair of it should it 
be broken. 

If this kind of knowledge were applied to all machines 
upon the farms and in the factories, they would do their 
work better for a longer time, at less expense and save 
their owners a great deal of worry, time and repair 
bills. 

Some machines are so simple they can be under- 
stood at a glance, while others of complicated construc- 
tion, like a watch, harvester, steam engine, linotype ma- 
chine or a sewing machine, require careful study to under- 
stand their construction and remedy their ills. Ma- 
chines costing a great deal of money are given expert 
care and attention to keep them in order and preserve 
them. 

The human body is the most wonderful machine in the 
world. It is made up of millions of parts which work 
in harmony; it furnishes its power, wears out millions 
of parts every day and replaces them with new ones 
which it makes; it fights its battles with disease and 
superintends all its operations within itself; it has time 
left to gird the earth with the railroads, telephones, and 
telegraph and give us literature, music, arts and sciences 
and direct all the human activities of commerce and so- 
ciety. 

17 



18 PHYSIOLOGY, HYGIENE AND SANITATION 

A practical knowledge of the human body will be 
gained by the study of it as a machine. 

Our happiness and success in life depend upon our 
good health. The body is said to be in good health when 
all its parts are doing their duty perfectly and in har- 
mony. 

One may spend long years of study and a great deal 
of money to secure a good education, yet, if he fails to 
care for his body and protect it against its enemies, his 
efforts may be wasted because of ill health or he may die 
from a disease which can be avoided. Recall six of the 
most successful people you know. How many of them 
have been sickly all their lives? 

Sickness or illness is that condition of the body in 
which some of the parts are not doing their duty per- 
fectly and in harmony. 

The human body is such a complicated machine that 
thousands of men have spent their whole lives in its 
study and were never able to learn all about it. If all 
the books and papers that were ever written about the 
body were collected in one place, it would take a life- 
time to count them. 

The science or study of medicine includes all that is 
known of the human body. Those who devote a great 
deal of study to this science are called Doctors of Medi- 
cine. They are required to study the physiology, hygiene 
and pathology of the human body and many other 
branches of the science. Each of these subjects and many 
other branches of the science require a large book of more 
than a thousand pages to tell what is known of the body. 

The purpose of this book is to give us enough knowl- 
edge of the physiology, anatomy, hygiene and pathology 
of our body to keep it well by obeying the laws of health. 



THE HUMAN BODY A MACHINE 19 

Anatomy is the study of the parts of the body. 

Physiology is the study of the functions or uses of the 
parts of the body. Hygiene is the study of the laws of 
health. Pathology is the study of the diseases of the 
body or the conditions which make the body sick. 

If we could imagine that these terms could be applied 
to a watch, for example, the physiology of the watch 
would tell us of the function or work of its parts. The 
wheels, moved by the spring, would turn the long and 
short hand to the letters or figures on the dial to tell the 
time of day, while the second hand moves around on the 
axle of one of the wheels to warn us of the passing min- 
ute. The anatomy of the watch would describe the parts ; 
the wheels, spring, long and short hand, the dial or 
face, second hand, axles, etc. The hygiene of the watch 
would give us the rules to keep it in repair and directions 
to keep it from running too fast or too slow. The " path- 
ology' ' would describe a broken spring or jewel, axle or 
any of the "diseases" which would hinder it from keep- 
ing the correct time. 

Summary 

A study of its use, the parts of which it is composed 
and their uses, the method of its operation and its motive 
power, its repair and its care constitute a practical 
knowledge of any machine. 

The human body is best studied as a machine to ac- 
quire a practical knowledge of it. 

The complete knowledge of the body is embraced in 
the science of medicine. 

Well-trained physicians are experts in the care of the 
body because they have a practical knowledge of the 



20 PHYSIOLOGY, HYGIENE AND SANITATION 

anatomy, physiology, hygiene and pathology and other 
branches of the science relating to the care of the body. 

The purpose of this book is to give one enough knowl- 
edge of his body to keep it well and protect it against 
its enemies. 

Questions 

1. Why is the human body like a machine? 

2. What are the necessary things to know about a ma- 
chine? The body? 

3. Why is it necessary to study the human body? 

4. Which is most to be desired, a splendid education, 
wealth or good health? Why? 

5. What makes you think the body is a complicated 
machine ? 

6. What is health? Sickness? 

7. What is the purpose of this book? 

8. Describe what may be called the physiology of a 
sewing machine; its anatomy, hygiene, pathology; a 
steam engine; an automobile; a school. 

9. Tell what we mean by the physiology, anatomy, hy- 
giene and pathology of the human body. 

10. Mention five things the human body does within it- 
self. 

11. Name five things which you think are the greatest 
the human machine has done for us. 



CHAPTER II 

THE SYSTEMS OF THE BODY 

Gross Anatomy. Viewing the body as a whole, it is 
found to consist of three divisions; the head, trunk 
and limbs. The head is made up of the cranium and the 
face, and contains the brain and organs of special 
senses — the eyes, ears, nose and the tongue. The trunk 
is made up of two parts; the chest, which contains the 
heart and lungs, and the abdomen, which contains the 
stomach, liver, intestines and other organs of digestion. 
The limbs are described as the upper and lower extrem- 
ities, or the arms and legs. 

The examination of the materials composing the body 
shows that it is made of bones, muscles, fat, blood vessels, 
blood, lymph, nerves, cartilage, connective tissue and 
skin. 

The bones, muscles, blood and other parts of the 
body have certain duties to do. Each system has a spe- 
cial task to perform. 

It is necessary to study the body by systems in order 
to get a knowledge of its parts, use and care. 

The Systems of the Body. A system of the human 
body is any group of parts w T hich perform in perfect 
order their particular duty. There are seven great sys- 
tems of the human body. The muscular system gives to 
the body its power of movement; the osseous or bony 
system gives to the body its shape and rigidity; the 
digestive system prepares the food which is converted 
into force and flesh. 

The circulatory system carries the blood and lymph 

21 



22 PHYSIOLOGY, HYGIENE AND SANITATION 

to all parts of the body; the respiratory system fur- 
nishes means for supplying the body with air and rid- 
ding it of certain poisons; the excretory system rids 
the body of its refuse matter and poisons, and the 
nervous system controls and guides all the work of 
the body. 

Each of these systems will be studied separately, but 
it must be remembered that all are so closely connected 
and work in such perfect unity that if one system be- 
comes impaired it will affect the work of all of them. 
Thus, if a bone is broken, it interferes not only with the 
work of the muscles but the work of all of the systems 
of the body. 

Organs. Any part of the body which has a special 
task to perform is called an organ. Thus, the heart is 
the organ which pumps the blood. The stomach is the 
organ which helps digest the food. The lungs are the 
organ which purify the blood by exchanging oxygen 
of the air for poisonous gases. The brain is the organ 
which helps to control the workings of the body. The 
eye is the organ of sight and the ear of hearing. One 
cannot live if the heart or lungs or brain stop working 
for even a short length of time. These three organs have 
been called "The Tripod of Life." 

The steam engine may be powerful enough when work- 
ing properly to draw a heavy train of cars, yet, if one 
of the wheels break, the throttle refuse to work, or 
the boiler sustain a serious leak, not only the engine 
but the entire train will be brought to a stop until re- 
pairs are made. That engine is useful and powerful 
only so long as all of its parts are performing their 
duties perfectly and in order. 

It is so with the human body ; it may be digesting its 



THE SYSTEMS OF THE BODY 23 

food, moving itself about, breathing regularly, pump- 
ing its blood, ridding itself of poison and governing its 
operations, yet, if part of it is injured by a severe blow, 
cut, frozen or becomes poisoned by disease germs, or 
for any other reason is seriously damaged, the entire 
work of the body is halted or stopped until repair is 
made. 

It is important that we protect the body from acci- 
dents or other injuries, and it is of special importance 
that the body be protected from sickness which is caused 
by impure air, food and water and other diseases which 
can be avoided. 

Sickness. A great deal of sickness and many of the 
deaths that occur are caused by diseases practically pre- 
ventable, and among these are tuberculosis or consump- 
tion, typhoid fever, small-pox, scarlet fever, measles, 
whooping cough, la grippe, influenza (sometimes called 
Spanish influenza) and "summer complaint of children." 
These and other diseases will be studied under the sys- 
tems of the body which are directly affected, but it must 
be borne in mind that any disease affects the work of 
the entire body. In no other way is the truth of the 
motto, "United we stand, divided we fall," better shown 
than in the work of the systems of the human body. 

Summary 

The gross anatomy of the body shows it to be of three 
main divisions, the head, trunk and limbs, and that it 
is composed of bone, blood, lymph, muscles, tendons, 
fat, blood vessels, connective tissue, nerves and skin. 

It is found to consist of a number of systems, each of 
which performs a special task. In health all the systems 



24 PHYSIOLOGY, HYGIENE AND SANITATION 

of the body perform their tasks in conjunction with 
each other. 

Any interference with a single system hinders the 
work of every other part of the body. Many diseases 
and accidents are preventable, and it is our duty to avoid 
them. 

Questions 

1. "What is meant by gross anatomy? 

2. Name three divisions of the body and their parts. 

3. "What materials compose the body? 

4. What is meant by a system of the body? 

5. Name seven systems of the body. 

6. Describe the physiology of 'the muscular system, 
the osseous system, the digestive system and the other 
four which are mentioned. 

7. What is an organ? Name three which are called 
"The Tripod of Life." Why? 

8. Name four other organs of the body and their 
functions. 

9. Explain what is meant by saying, "The work of 
the body may be likened to the work done by a machine." 

10. Name five rules for general hygiene of the body 
given in this chapter. 

11. What is meant by preventable sickness? How 
may such sickness be avoided? 

12. Name nine diseases which can be prevented. 

13. Where in this book will they be described? 

14. What is the motto which applies to the work of 
the systems of the body? 



CHAPTER III 



BODY CELLS 



Minute Anatomy. In the last chapter the gross anat 
omy of the body was considered. The eye unaided by 
any instrument is able to see that the body is composed 
of bone, blood, muscles, nerves, skin, etc. To under- 
stand fully the workings of the 
body and how to protect it, it 
is necessary to take a closer 
view of the parts and see how 
they are constructed. They are 
made up of objects so small 
that they cannot .be seen with 
the eye alone, but can be seen 
only with the aid of the mi- 
croscope. Such an examina- 
tion of an object is termed a 
microscopical examination. 

When an object is seen at a 
distance of several miles it may 
be difficult to say whether it is 
a dwelling, barn or some other 
object. Upon coming closer 
to it, we see it is made of bricks and we can see the mor- 
tar between them. Upon examination, we may see the 
grains of sand in the mortar. With the aid of different 
lenses these grains of sand may be enlarged until they 
appear as great stones. 

Blood when examined by a microscope is found to con- 
tain millions of tiny round objects called cells. Likewise, 

25 




Pigr. 1. — A microscope 
with which to magnify 
objects too small to be 
seen with the unaided 
eye. 



26 PHYSIOLOGY, HYGIENE AND SANITATION 




the bones, muscles, fat, skin, nerves, blood vessels and 
every part of the body are found to be made up of a 
great many tiny parts, so small usually 
that many hundreds would have to be 
placed end to end to reach an inch. All 
these tiny parts are called cells. A cell 
is known as the smallest division of liv- 
ing matter. In health, each cell retains 
its own identity ; that is, a blood cell 
never becomes a fat cell or a bone cell or 
a muscle cell, neither does any cell be- 
Fiff. 2.— Blood come a cell of another tissue. A tissue is 

cells (magni- . . . 

fied) in a small any part of a living body which is made 

blood vessel. 

up of cells. 
The body is a mass of cells which make up the bones, 

muscles, nerves, blood, fat, blood vessels, skin and other 

tissues of which the body is composed. 

The human body, like all other animals 
and plants which are found upon the 
earth, starts from a single cell, and, by 
dividing and growing, forms the entire 
body. The body is repaired by replacing 
new cells for those injured or worn out. 
Every motion of the body, every thought, 
every act of the body causes many cells 
to be destroyed. 

Good health depends upon good cells. 
When the body is in good health new 

cells are formed at once to take the place of those worn 

out or injured. 

In sickness, cells are destroyed much faster than new 

ones can be made to take their places. When too many 

cells are destroyed death of all the cells occurs and the 

body is said to be dead. A person who is recovering 




Fig-. 3.— A high- 
ly magnified 
body cell. 



BODY CELLS 



27 




Fig-. 4.— The man looks 
"thin." The germs of tu- 
berculosis (consumption) 
have destroyed millions of 
his body cells". 



from a severe injury or ill- 
ness is said to "look thin" 
or to have "lost flesh." This 
is only another way of say- 
ing that many more cells 
have been destroyed during 
his sickness than have been 
made to take their places. 

Cell Enemies. Any condi- 
tion or habit which destroys 
cells faster than they can be 
replaced results in impair- 
ment of the body. Keeping- 
late hours at night deprives 
the body of the time to repair itself, and a person per- 
sisting in this habit be- 
comes less efficient or 
ill. In the same way, 
the body is affected by 
bad air, water and 
food, by alcoholic 
drinks and exposure to 
too much heat or cold 
and accidents. 

Germs or bacteria 
are responsible for 
more than one-half of 
all the sickness of the 
world. They are, there- 
fore, the worst of the 
cell enemies. They are 
microscopical in size, being so small that many thousands 
laid side by side will not cover the distance of one inch. 




Pig-. 5.— The tiny dots are "germs 
or bacteria" in blood. The larger 
bodies are blood cells (highly 
magnified). 



''■'■:...■:■ ■■■ 

.: :;■ ' ^ ■ . '. : : 
■«£. .-.^ ■?,;■■■■ -.■;;;:■;. r y 




28 PHYSIOLOGY, HYGIENE AND SANITATION 

Summary 

Minute Anatomy is a branch of science which treats of 
the smallest parts of which the body is composed. Such 
a study can be made only with the microscope, an in- 
strument of many len- 
ses which has the power 
to magnify an object 
and make it appear 
much larger than it is. 

The cells composing 
the entire body are 
readily seen with such 
an instrument and the 
difference in size, shape, 
color or texture may be 
observed. 

The body is constant- 
ly being destroyed by 
loss of cells. In health 
they are replaced immediately. 

Sickness and death are caused by cells being destroyed 
faster than they can be replaced. 

Consumption or tuberculosis, typhoid fever, pneumonia 
and diphtheria and all the diseases which are called 
"catching" are caused by bacteria or germs, which are 
the worst of all cell enemies. 

Questions 

1. What is minute anatomy and how does it differ from 
gross anatomy? 

2. Explain what is meant by a microscopical examina- 
tion of things. 



Fig. 6.— The dotted lines point to 
two parts of the lung: which 
have been destroyed by the 
germs of "consumption." 



BODY CELLS 29 

3. What is a cell? Name six kinds of cells in the body. 

4. How is the body repaired? How destroyed? 

5. What happens to the body cells in health? In sick- 
ness? 

6. What is meant by a person "looking thin?" Being 
dead? 

7. Name seven cell enemies. How do they effect a per- 
son? 

8. What cell enemies are responsible for more than 
one-half the sickness of the world? 

9. Recall ten people you know who have been sick or 
who have died. How many of them were sick or died of 
the disease which yon know can and ought to be pre- 
vented ? 



CHAPTER IV 

CELL ENEMIES 

Bacteria. Germs or bacteria are found everywhere in 
nature; in the air, water, and soil. They belong to the 
vegetable kingdom and are the lowest form of vegetable 
life. They are made up of single cells, microscopical in 
size, and increase with great rapidity under proper con- 
ditions. There are many thousands of kinds of bacteria, 
most of which are entirely harmless to the human body. 
A great many bacteria are helpful while a few produce 
diseases when they get into the body and grow. 

Helpful Bacteria, If a clover plant is pulled from the 
ground, there will be found, probably, little white balls 
or nodules attached to the roots. If a piece of this nodule 
is placed under the microscope it will be found to con- 
tain a great number of bacteria which gather nitrogen 
from the air and hold it in the soil. For this reason the 
cultivation of clover, soy beans and cow peas and other 
leguminous plants is undertaken to improve the quality 
of the soil. Without the presence of these germs, the 
growth of these crops would be far less valuable. 

The United States Department of Agriculture will 
furnish the farmers a supply of these germs and direc- 
tions how to grow them. Before sowing clover seed, 
cow peas or soy beans they are sprinkled with a fluid 
containing these germs so that when the plant grows 
these bacteria will be in the soil, which will add to the 
value of the crop. 

Besides these helpful bacteria, a great many bacteria 
aid in destroying dead animals and other refuse matter 
so that we are rid of a great many unpleasant odors and 

30 



CELL ENEMIES 



31 



disgusting sights. The sewage or wastes of any city, 
community or family may be safely disposed of by 
allowing certain bacteria to destroy it. 

The yeast plant is one of the best known germs, being 
used in homes to make bread. All fermentation is 
caused by the growth of this tiny plant. 

Helpful bacteria are used in the manufacture of 
cheese and butter. Their growth in milk is responsible 
for its souring. A drop of sour milk placed under the 
microscope will reveal thousands of bacteria. Butter- 
milk, one of the best of foods, contains millions of bac- 
teria which are responsible for its flavor. Such germs 
have been called "friendly germs/' 

Harmless Bac- 
teria. Most of the 
bacteria found in 
nature are harm- 
less. "Water taken 
from ponds, cis- 
terns and wells 
might contain a 
large number of 
different kinds of 
bacteria, and yet 
not always be 
harmful if taken 
into the body. 
Their presence in 
drinking water, 
however, is a sign 

of danger, and it should not be used, unless thoroughly 
boiled. 

Harmful Bacteria. A few of the bacteria are known to 




Figr. 7.— Yeast cells as they grow in "home- 
made" yeast bread. 



32 PHYSIOLOGY, HYGIENE AND SANITATION 

produce diseases when they are planted and grown in 
the body. They may be called the "seed of diseases." 
They are also called pathogenic bacteria. Open sores upon 
the body, "boils/ 7 "pimples/ 7 erysipelas, "blood poison/' 
tuberculosis, diphtheria, membranous croup, typhoid fever, 
dysentery (flux), "summer complaint of children/ 7 pneu- 
monia, la grippe, "granulated lids, 77 "sore eyes/ 7 and 
many other diseases are caused by these microscopical 
plants getting into the body and destroying cells and 
many times some of them destroy enough cells to cause 
death. In the same way it may be said that measles, 



a b c 

Pig - . 8.— A. round germs (cocci); B. rod-shaped germs 
(bacilli); C. spiral-shaped germs (spirilla). 

scarlet fever, whooping cough, small-pox, chicken-pox and 
mumps are caused by the growth in the body of bacteria. 
A bacterium is usually so small that thousands of them 
can find room in a drop of water hanging from the point 
of a needle. They are from one-ten-thousandths to one- 
twenty-thousandths of an inch thick, or, in other words, 
about five hundred of them laid side by side would not 
cover more space than the thickness of a hair. They can 
only be seen as small objects when placed between thin 
pieces of glass under a microscope which will make them 
appear to be seven or eight hundred times larger than 



CELL ENEMIES 33 

they really are. Even then they look to be no thicker 
than the dot of an "i" on this page. 

Shapes of Bacteria. A germ may be round like a grape 
or marble, in which case they are called cocci (singular 
coccus). Some are shaped like a small piece of pencil, 
in which case they are called bacilli (singular bacillus), 
or they may have the shape of a spiral like a corkscrew, 
in which case they are called spirilla (singular spirillum). 

Summary 

Germs or bacteria are the smallest form of vegetable 
life, and are found everywhere in nature. They are of 
the simplest construction, being a single cell. 

Most of them are harmless to men. Many of them are 
friendly to man, and few produce diseases when they 
grow in the body. 

Helpful bacteria are used to enrich the soil, to make 
bread, cheese .and butter. They may be used to make 
harmless the wastes from a city or home and to destroy 
decaying animal or vegetable matter. 

They are of three shapes and are named the coccus, 
bacillus and spirillum. 

Water from ponds, wells and cisterns may contain 
many bacteria that are harmless. Such water contains 
surface water, and should not be used for drinking or 
cooking purposes. When disease germs are deposited 
near such places, a person drinking the water may de- 
velop typhoid fever or other diseases. 

Disease germs are called the "seed of disease' ' and 
when planted in the body may cause typhoid fever, 
tuberculosis, consumption, diphtheria, membranous 
croup, whooping cough, scarlet fever, "granulated lids," 



Phy.— 2 



34 PHYSIOLOGY, HYGIENE AND SANITATION 

"sore eyes/' pneumonia, la grippe, "bad colds," small- 
pox, chicken-pox, and many others. Such germs are 
called pathogenic bacteria. 

Questions 

1. What is a germ or bacterium? Illustrate the size 
of bacteria. 

2. What shapes may germs have? What is a coccus? 
What is one called when shaped like a fire cracker? A 
spiral ? 

3. Where are harmless bacteria sometimes found? What 
is the danger of finding them there ? How can you know 
a well or cistern receives surface water? 

4. What are nitrifying bacteria, and where may they 
be found? What is their value? 

5. How may nitrifying bacteria be sown in the soil? 

6. Name five helpful things which bacteria do ? 

7. What do we mean by the "seed of disease"? What 
is another name for them? 

8. Name fifteen diseases which they produce? What is 
necessary before they can produce these diseases in the 
body? 



CHAPTER V 

BACTERIA 



How to Grow Bacteria. If a small piece of yeast cake 
which contains the yeast plant or germ be placed in a 
bottle with a thin mixture of water and boiled potato 
and set in a warm, dark 
place, there will be seen 
bubbles of gas (carbonic- 
acid gas) form on top of 
the mixture. This is caus- 
ed by the growth and re- 
production of yeast plants. 
In a few hours there 
would be found many 
thousand times the number 
planted. ' i Home-made ' ' 
yeast bread can be made 
beginning in this manner. 

Growth of Germs. Germs 
grow only in the presence 
of moisture, food, warmth 
and absence of sunlight. 
The germ of "life in a grain 
of wheat, corn or other 
seed, is kept from growing 
for many months or years 
because most of the mois- 
ture in the grain has been removed. (Weigh carefully a 
dry grain of corn. Place in a box of good soil which is 
kept in a warm place. In five days weigh it again and 

35 




Fig-. 9.— Germs of tubercu- 
losis grown in a pint flask. 
Countless millions are seen 
in the white mass floating- 
in the bottle. 



36 PHYSIOLOGY, HYGIENE AND SANITATION 

see how much it has gained in weight by absorbing water. 
See if the germ is growing.) 

(Place a piece of yeast cake in some dry flour and 
keep in a dry, warm place. See if it grows in twenty- 
four hours. "Why? Make a thin paste of some flour 
and water and place some of the yeast cake in it. Set 
it in a warm, dark place and examine after twenty-four 
hours. What happened? Why?) Apples and other 
fruit " spoil" by reason of destructive germs growing in 
them. If enough moisture is extracted from such fruit 
it may be kept from "spoiling" for a long time when 
kept in a dry place. Why is it necessary to keep in a 
dry place? Such fruit is called "dried fruit," "evapor- 
ated fruit" or "dehydrated fruit." New string beans 
may be kept for winter use by exposing them in an oven 
to a uniform heat sufficient to dry them. Why? 

Most germs when once dried are dead and will not 
take on new life when placed in proper conditions for 
their growth. 

Food of Germs. A grain of wheat, corn or other 
seed contains in the "heart'" the germ of its life. Nature 
has surrounded it with food to last until it begins send- 
ing out roots into the soil to get its water and food. 

Place ten grains of corn in a clean saucer, fill it half 
full of clean pebbles, pour in water until it covers the 
stones. Watch from day to day and note how long it 
will be before the plant uses up all the food. Why did 
they grow at all? Why did they die? How would you 
have continued their life? 

Bacteria, like all other living plants or animals, must 
be supplied with food. Milk, thin soups, blood serum, 
gelatine, raw potato and fresh meats are some of the 
foods which will supply many bacteria with food. 



BACTERIA 37 

Warmth for Germs. Place a few grains of wheat or 
corn in a small box of good soil which is moist. Place it 
where it will be cold and see if it will grow. Place a 
piece of yeast cake in the potato and water mixture and 
set it in an ice box for twenty-four hours. What hap- 
pened? Why? 

Seed which lie in the ground through the winter 
months begin to grow when the sun furnishes them 
sufficient heat. All the conditions necessary for their 
growth except warmth were present during the cold 
months. Germs, like the higher form of vegetable life, 
will not grow unless they are supplied with warmth. 

Absence of Sunlight. Most plants require sunlight for 
their growth. Bacteria are so delicate in their structure 
that most of them are killed when exposed for some time 
to the light of the sun. They grow better in dark places. 
The diseases which are caused by germs are more likely 
to develop in homes and rooms which do not admit sun- 
light. 

In sunshine, nature has given us one of the cheapest 
ways to kill disease germs, and to protect ourselves 
against sickness which they cause. Bed clothing, rugs, 
carpets, curtains and clothing should be exposed for a 
few hours to the strong sunlight every few days to 
purify them. This should be done in every case when 
one is ill, has recovered or has died from one of the 
"catching" or germ diseases. Many lives that are now 
being lost from "consumption," typhoid fever, scarlet 
fever, measles, etc., could be saved if every one would 
use this simple means of killing the "seed of disease," 
and much sickness and suffering could be prevented. 

How Disease Germs Are Spread. Bacteria produce 
sickness by growing in the body where there are warmth, 



38 PHYSIOLOGY, HYGIENE AND SANITATION 



food, moisture, and absence of sunlight. They grow and 
multiply very rapidly and throw off poisons which con- 
sume the body cells and many times cause death. 

Disease germs may escape from the body through the 
nose, skin, lungs, throat, bowels or kidneys. The germ 
of consumption (tuberculosis), for example, will escape 

from the lungs through 




&tiii 



the mouth or nose in most 
cases, although the germ 
may attack any part of 
the body, in which case it 
may escape in other ways. 
It is impossible for any 
person to "catch" one of 
these diseases unless the 
seed or germ of it is plac- 
ed in the body and grows. 
It is no more possible to 
have typhoid fever, for 
instance, without swallow- 
ing some of the seed or 

germs than it is to grow a stalk of corn without planting 

the grain of corn. 

There are many ways by which "seed of diseases" 
may be scattered and planted in the body. They may 
be found in impure air, water, milk, or other food or soil. 
They can be carried by flies, rats, cats, mice, drinking 
cups, towels, wash basins, unclean hands and many 
other ways. 

How Germs Are Killed. Bacteria and germs are best 
killed by burning or boiling. Any living thing when ex- 
posed to intense heat is finally killed. Germs, therefore, 



Fig-. 10.— Germs or "seed" of 
"lock-jaw" (tetanus). Notice the 
club-shape. 



BACTERIA 



39 



being very delicate living plants, are easily killed with 
heat. 

Bedclothing, wearing apparel, dishes, 
knives, forks, spoons and drinking glasses, 
used by a person ill of one of the germ 
diseases, should be boiled for fifteen or 
twenty minutes before being used by any 
other person. Every person who has been 
ill or who has died of tuberculosis, ty- 
phoid fever, diphtheria, or any of the 
germ diseases, was made sick because the 
seed of the disease from some one else 
were not destroyed. 

Summary 

Germs will grow in the presence of 
moisture, food, warmth, and in the ab- 
sence of sunlight. 

The canning of fruits and vegetables is 
successful only when the knowledge of 
the growth and destruction of bacteria is 
applied to their preparation. "Dried 
fruits" and vegetables "keep" because 
most of the moisture has been reduced, and all the germs 
have been killed. 

The use of sunshine during and after sickness and after 
death from a preventable disease to purify the room and 
its contents helps prevent the spread of illness. 

Bacteria produce sickness and cause death by growing 
in large numbers in the body and making poisons which 
destroy the body cells. 




Fig-. 11.— Germs 
o f diphtheria 
grown in a test 
tube. Millions 
are in the mass. 
(A). 



40 PHYSIOLOGY, HYGIENE AND SANITATION 

Each disease is produced by a particular kind of germ, 
and it is impossible to be ill of such a disease unless that 
germ or seed is planted and grows in the body. 

Disease germs are scattered and sown in many ways; 
in water, milk, or other food, by flies, rodents, domestic 
animals, unclean hands, drinking cups, towels, and wash 
basins. 

Questions 

1. How can "yeast" be made for making "home- 
made" bread? 

2. What is yeast ? Is it a germ ? Why ? What are the 
conditions necessary to grow germs? 

3. What happens when a grain of corn, wheat or other 
seed are put in warm moist soil? What is nature's way 
of preserving seed? How do you account for the in- 
crease in weight after a seed has been planted in the 
ground for a time? 

4. Why does "dried fruit" keep? What is meant by 
"keeping?" 

5. What causes canned tomatoes or other fruit to 
' ' spoil ? ' ' How is this prevented ? Why ? 

6. Why will not apples, peaches or other fruit rot or 
sour w T hen they are cut in small pieces and scattered and 
exposed to the hot sunshine for a few days ? 

7. What is nature's way of killing germs? How would 
you apply this fact in your home in sickness caused by 
germs ? 

8. How do the pathogenic germs or the "seed of dis- 
ease" produce sickness and death? 

9. Can one become ill of "consumption" by getting into 
his body the germs of typhoid fever? Why? 

10. How are germs scattered? 



BACTERIA 41 

11. Explain at least four ways by which disease germs 
may be prevented from growing in the body. There are 
four more laws of hygiene in the same paragraph. What 
are they? 

12. What is the best way to kill germs? 

13. How would you make safe for use, germ-laden cloth- 
ing, carpets and eating utensils? What diseases may 
be spread by such things, if not properly handled? 

14. Why do the germ diseases continue to cause illness 
and death of our people? 

15. In what other ways may disease germs be killed? 



CHAPTER VI 



THE OSSEOUS SYSTEM— THE SKELETON 




Uses of the Bones. The bones have three important 
uses. First, they are the framework of the body and 

give it support and retain its 
shape. The bones being hard 
and more or less rigid, the 
shape of the body after full 
development remains about 
the same from year to year. 
From birth to the age of 
twenty-two to twenty-five 
years the bones grow in 
length and size. 

Second, the bones act as 
levers upon which the mus- 
cles act to produce motion. 
Without the bones the body 
would be a shapeless mass of flesh and would flatten like 
wet clothes when laid upon the floor. The muscles, which 
act like rubber bands when stretched, would be unable 
to move the body about because there would be no rigid 
support for them to pull against. If one tried to move 
the arm without the bones in it, it would bend in every 
direction like a half -stuffed stocking. The fingers without 
bones would be like small rolls of soft pulling-candy and 
refuse to do their thousands of operations. 

Third, the bones help protect the delicate organs. The 
eye, for example, is set in a bony casing so that it is well 



Fig". 12.— The shoulder blade 
(scapula). It is broad and 
flat for the attachment of 
muscles. 



THE OSSEOUS SYSTEM— THE SKELETON 43 



protected from blows, etc. 
of all organs, is placed in 
a bony box so that it may 
be secure from ordinary 
falls, knocks and crushes. 

The heart and lungs are 
placed in a cage of bones 
(the ribs) so that they 
may do their work without 
being molested. The large 
arteries which carry the 
life-saving blood, usually, 
are placed under the shel- 
ter of bones so they will 
not be easily cut into or 
broken apart. 

The spinal cord, that 
wonderful branch of the 
brain which controls, with- 
out our conscious knowl- 
edge, thousands of impor- 
tant operations of the 
body, is placed within a 
tunnel hollowed out of 
many solid bones which 
work easily upon one an- 
other without injury to 
the delicate organ within. 
This column of bones is 
known as the spinal col- 
umn. 



The brain, the most delicate 




Fig-. 13.— The long- bone (femur) 
of the thigh. Note its large 
ends. The upper end is 
round and unites with the 
hip bone with a "ball and 
socket" joint. Its lower end 
makes a hinge-joint at the 
knee. 



Kinds of Bones as to Shape. When the numberless 
activities of the body are considered, it is evident there 



44 PHYSIOLOGY, HYGIENE AND SANITATION 



must be bones of various 
sizes, shapes, and lengths. 

There are flat bones for 
protecting delicate organs 
and furnishing a broad 
base for the attachment 
of muscles; for example, 
the shoulder blades and 
bones of the skull. 

There are short, thick 
bones for strength to 
support the body, as the 
bones of the foot; long 
heavy bones for speed 
and strength, as the bones 
of the arm and thigh; 
short slender bones for 
speed and delicate opera- 
tions, as the bones of the 
fingers ; long slender bones 
for protection of delicate 
organs and muscular at- 
tachment, as the ribs 
which with part of the 
spinal column and the 
breast bone (the sternum; 
form the chest. Some 
bones are irregular in 
shape, as the bones of the 
spinal column. 

The bones of the body, about two hundred and six 
in number, are arranged to give the greatest usefulness 
and strength with least bulk and weight. To give 




Fig-. 14.— The spinal column 
through the hollow of which 
runs the spinal cord. 



THE OSSEOUS SYSTEM— THE SKELETON 45 

strength and as little weight as possible, many bones are 
hollow for almost their entire length. 

The longer bones of the limbs are so constructed. If 
a piece of paper be rolled into a hollow cylinder and each 
end set upon a block, it will require considerable force to 




Fig. 15.— The chest or "bony cage'' for the attach- 
ment of muscles, and protection of delicate organs 
(lungs, heart, liver). 



break it. The same amount of paper made into a solid 
piece would be far less strong. 

If a bar of iron as long as a piece. of hollow pipe and 
weighing just as much is placed upon two supports, it 
will be found that the cylinder of iron will support with- 
out bending much more weight than the solid bar. 



46 PHYSIOLOGY, HYGIENE AND SANITATION 



If the bones of the arm or leg, for example, were one 
solid piece of bone and weighed no more than they now 

do, they would 
break very easily 
and would hardly 
support the weight 
of the body. If 
they were solid 
and large enough 
to support the 
body, they would 
be so large they 
wouldmakeit 
look clumsy and 
produce slow and 
awkward move- 
ments. 

Joints. To sup- 
port the body all 
its bones must be 
joined together. 
Some bones have 
no motion at their 
joints which are called immovable joints; for example, 
the bones which form the skull. 

Many bones move freely upon one another by means 
of movable joints. When motion is in two directions 
only, the bones work upon one another by means of the 
hinge joint. When motion is required in all directions a 
ball and socket joint is used. Where there is a great va- 
riety of movement required, as in the wrist, a compound 
joint is employed. 

Bones near the joints are made larger so that the 
muscles can act with greater power in moving the bones. 




Fig - . 16. — The bones of the head and 
face. Observe the bony sockets to 
protect the eye-balls. 



THE OSSEOUS SYSTEM— THE SKELETON 47 

If the bones were the same size all the way up to the 
joint, much of the power would be lost in pulling the 
bones together. Take two sticks with square ends and 
lay them on the table end to end. Fasten a string close 
to one side and bring it straight down the side to the 
end of the other stick. Pull the string in this straight 
line and note how hard a pull it takes to break the joint. 




Fig - . 17.— The bones of the hip (the pelvis). Note the strong- 
bands of connective tissue holding the bones together. 



Place a piece of chalk near the joint under the string 
and pull the string as before and see if the joint breaks 
easier. 

The tendons which are the tough cords forming ends of 
the muscles, work over these enlargements and do the 
work of the muscles with greater ease. Bones are covered 



48 PHYSIOLOGY, HYGIENE AND SANITATION 



with a tough glistening membrane called periosteum 
which is inelastic. 

Between the joints, cartilage is placed to serve as pads 
or cushions to prevent jarring when the body is in mo- 
tion. These pads of cartilage are covered with a synovial 
membrane. 

To prevent friction and insure a smooth, noiseless work- 
ing of the bones the synovial membrane and the tendons 
working over the joints are kept lubricated, " oiled," by 
synovial fluid. 

Structure of Bones. In early childhood the bones are 
much more soft and spongy than in later years. This is 
a wise provision of nature to protect the child, for the 

bones being spongy 
will not break as 
easily as if they were 
hard and brittle like 
a piece of chalk. In 
old age a slight fall 
will often cause a 
serious break in a 
bone because the 
animal matter which 
gives to the bone its 
elasticity in youth 
has largely disappeared and it is composed mostly of 
mineral matter which is hard and brittle. If a fresh bone 
is put into a grate of live coals for an hour, the animal 
matter will be consumed and the bone will consist of min- 
eral matter when it may be easily crushed like chalk. 

If a bone be soaked for several days in strong vinegar 
or diluted muriatic acid, the mineral matter will be re- 




Fig-. 18.— A thin slice of bone greatly 
magnified showing the canals and 
passages for the nerves and blood 
vessels. A. Haversian canal. 



THE OSSEOUS SYSTEM— THE SKELETON 49 

moved and the bone may be bent or eVen tied in a knot 
because it contains mostly the animal matter. 

A bone when sawed across is seen to be hollow and to 
contain fat which is called marrow. Blood vessels and 
nerves are also found in bone marrow. It is found to be 
spongy and filled with tiny holes. These are the mouths 
of the Haversian Canals which in health allow blood ves- 
sels and nerves to reach every part of a bone. 

If a thin piece of bone not larger than the head of a 
pin be put under the microscope, these tiny canals may 
be seen and even smaller ones branching out to feed the 
bone cells of which every bone is composed. 

Summary 

Giving to the body its shape and support, protecting 
delicate organs, and serving as levers for the action of 
muscles, comprise the three most important uses of the 
skeleton. 

Bones are short, long, flat or irregular according to the 
use for which they are intended. Some are for strength 
and speed, some for attachment of muscles and supporting 
weight, some for protecting delicate organs and some for 
speed and dexterity. 

Many bones are hollow to give the greatest strength 
with least weight. 

Joints are either movable or immovable and enable 
the parts of the body to bend and move about. Without 
movable joints the human body would be stiff like a 
tree. The hinge, ball and socket and compound or glid- 
ing joint give to the body all its motions. 

The jarring of the body is prevented by cartilage be- 
ing placed between the bones, and by the use of curves 
in the erection of the skeleton. 

Bones are composed of animal and mineral matter, and 



50 PHYSIOLOGY, HYGIENE AND SANITATION 



these are responsible for the difference in hardness of the 
bones of the young and old. 

Bones are nourished by blood which reaches the cells 
through the blood vessels in the marrow and canals. 

Questions 

1. What are the uses of the bones of which the skeleton 
is composed? 

2. What would happen to your body if by some means 
your bones could be suddenly removed? Would your 
head feel hard? Why? How tall would you be? 

3. What kind of bones are there as to shape? 

4. Why are the bones of the foot short and thick? Why 
are the bones of the arm and leg long and strong ? 

5. Why are some bones hollow? Why is a wheat straw 
hollow? Why do men use hollow steel tubes in build- 
ing bicycles? 

6. What are joints? Why are joints? 

7. What are movable joints? Immovable joints V 

8. How many kinds of movable joints are there? 

9. Give an example of each. 

10. Why are bones made larger near the movable joints? 
How can you prove this? 

11. What are tendons? 

12. What is cartilage for? Where is it found? 

13. What is the periosteum ? The synovial membrane ? 

14. What keeps the joints from "screaking" and wear- 
ing when they move? 

15. Why should the bones of children be soft? 

16. What gives hardness to bones? Why do the bones 
of an aged man break easier than a child's? 

17. Does blood flow through every part of a bone? 
How? 

18. How are bone cells fed? Can the bone cells be 
seen with the naked eye? 



CHAPTER VII 

HYGIENE OF THE OSSEOUS SYSTEM 

Care of the Bones. Bones require food which contains 
sufficient mineral matters, lime, salts, and phosphates. 
These are found in a general vegetable diet. Nursing in- 
fants who ought not to eat such things find these salts 
in their milk, if the mother selects the food which con- 
tain a large per cent of mineral salts. These will be dis- 
cussed in the chapter on Food and Digestion. 

When a baby receives too little bone food, a disease 
called rickets is likely to develop and careful attention 
to diet under the direction of a skilled physician is neces- 
sary. 

Bow-legs are often caused by eating too little bone- 
building food. It is often caused by encouraging very 
young children to stand on their feet too much while 
the bones are soft and pliable. Nature will usually put 
a child on its feet when the proper time comes and it is 
no special mark of distinction to have the child walking 
with bent legs earlier than other babies whose legs will 
be straight, if treated properly. 

Dislocations. A bone is sometimes thrown "out of 
joint" or dislocated by falls, blows, etc., and sometimes 
by the strong action of the muscles. It causes instant 
pain over the joint and the joint will not work in its 
usual way. The head of the bone can be felt out of its 
proper place and the ligaments are usually torn. When 
it is put in place, the joint, if a large one, should be 
kept at rest until the "soreness" disappears and then 
used carefully for a few weeks. 

It is always best to send for a physician to reduce the 
dislocation, for many joints have been badly injured by 

51 



52 PHYSIOLOGY, HYGIENE AND SANITATION 




ignorant but well-meaning people trying to put the bone 
back into its place. 

Sprains. When a joint is severely twisted the liga- 
ments are sometimes torn or broken loose but the bones 
may not be thrown out of place. This is exceedingly 

painful. Until the physi- 
cian arrives, the part may 
be placed in hot water, 
which will prevent too 
great a swelling. Cold 
water will sometimes be 
helpful, or both hot and 
cold may be used at dif- 
ferent times. If the joint 
may be suitably strapped 
or bandaged, the resultant 
swelling and pain are 
much less and early use of 
the joint be had. Sprains may keep one on canes and 
crutches for weeks without this kind of treatment, but 
with it one may be able to resume his duties in a few days. 

Fractures. A bone when broken is said to be fractured. 
This may be done by falling, jumping, blows, muscular 

effort, crushing in- 
juries, etc. There is 
always pain and 
loss of power to 
move the part. Often, 
if in a limb, the mem- 
ber seems to have an 
extra joint which 
marks the place of in- 
jury. The broken bone must not be moved about as the 



Fig-. 19,— A broken "wrist." A. 
Showing- how the hand looks 
with such a fracture. B. Show- 
ing the reason for the deform- 
ity. 




Pig". 20.— The proper way to splint 
the broken bones as shown in Fig. 

19. i .j^i 



HYGIENE OF THE OSSEOUS SYSTEM 53 

sharp edges might cut the nerves or blood vessels. A 
competent physician should be called at once, and the 
bone kept at rest until he arrives. The bone when set 
should remain at rest for several weeks until nature has 
made new bone cells to take the place of those destroyed, 
and the broken ends are united. 

Stooped Shoulders. This condition is caused by 
sitting, standing or sleeping so that the bones of the 
spinal column are kept bent forward in an unnatural 
position for a long time. The pads (cartiliages) between 
the bones become thinner on the inner side and thicker 
behind so that the bones are wedged in this position. 
It is a deformity that can be easily avoided by sitting 
and standing in an upright position and by sleeping with 
just enough pillows under the head to keep the head on 
a line with the body when lying on the side. 

Stooped shoulders cause the chest to become shallow 
and prevent the lungs from getting a full supply of air. 
Besides, it looks bad to see a young man or girl with 
shoulders stooped when by a little effort their carriage 
may become as erect as anybody's. It may be overcome 
by constant attention to see that the sitting and standing 
positions are correct ; that is, the shoulders should be 
held up and the back straightened. 

Deep breathing should be practiced several times daily, 
especially upon getting up in the morning. This is done 
by standing in an erect position with heels together and 
slowly breathing through the nose into the lungs all the 
fresh air possible and then allowing it to escape slowly 
through the nose. This should be repeated about twelve 
times a minute for five or ten minutes. This exercise 
done several times a day by all the pupils in school, with 
the windows and doors all open will drive away many a 



54 PHYSIOLOGY, HYGIENE AND SANITATION 

headache and give a brain, poisoned with bad air, new- 
power to do its work. 

Bone Felons. This is caused by one of the cell ene- 
mies, bacteria or germs. These tiny plants get under 
the periosteum and begin to grow and destroy bone 
cells. Felons usually occur on the fingers because they 
handle many things which contain the germs that get 
to the bone. The part swells, gets very red, is extremely 
painful and is considerably warmer than the rest of the 
body. 

Immersing the finger in hot water may relieve the pain 
some but the best treatment will be given by the physi- 
cian who, with a clean lance, will cut through the tough 
periosteum and allow the accumulated matter (pus and 
blood) to escape. The relief comes almost instantly. If 
this is not done, a joint or entire finger may be lost or 
blood poison may develop and the intense suffering will 
continue for days and sometimes weeks. 

Other Bone Diseases Caused by Germs. Inflammation 
of bones (osteomyelitis) is a severe infection caused by 
the growth of the common pus germs, and may cause 
death or loss of an arm or leg or other parts unless the 
surgeon cuts into the bone and makes a place for these 
germs and their poisons to drain out. 

White Swelling is an inflammation of the bones caused 
by the germ of consumption. It is a very serious condi- 
tion and requires the attention of the physician. 

Pott's Disease is an inflammation of the bones of the 
spinal column and is caused by the growth in them of 
the germ of tuberculosis (consumption). This germ 
causes parts of the bones to be destroyed so that the com- 
mon condition known as "hump back" results. 

It is a common saying that such a condition was 



HYGIENE OF THE OSSEOUS SYSTEM 55 

caused by a fall or other injury. In all cases it is a 
tuberculosis of the bone which often heals entirely, if 
the child or person is placed in the hands of a competent 
physician when the little knot first appears along the 
chain of bones of the spinal column. The patient will 
be placed in a jacket to hold the back stiff, at rest and 
in place. Such a child, when treated properly, will 
likely be saved from having a humped back. 

Summary 

Our food should contain enough mineral matter to 
make the bones hard. Vegetables contain a good quan- 
tity of mineral salts. Nursing mothers should eat plenty 
of bone building food so that the baby may receive suffi- 
cient mineral matter in its milk. 

Rickets in children is caused by a lack of mineral matter 
in the food for the bones. 

Bow-legs are caused by the child being allowed to 
stand upon its feet before there is enough mineral matter 
in the bones to keep them stiff. 

A bone "out of joint" is said to be dislocated and 
should be promptly reduced and treated by a physician. 

A broken bone is said to be fractured. It should not 
be moved about and must be "set" and cared for after- 
wards by a competent physician. 

A torn or detached ligament is called a sprain. Hot 
or cold water relieves the pain and proper strapping and 
bandaging by a physician will greatly shorten the time 
for recovery and relieve the pain. 

Stooped shoulders are a result of a bad habit and may 
be corrected by proper attention to the sitting, standing 
and sleeping position. 



56 PHYSIOLOGY, HYGIENE AND SANITATION 

Bone felons are caused by germs growing under the 
periosteum. The treatment consists in making a drain- 
age by having the doctor cut through the periosteum with 
a lance. 

"White swelling and Pott's disease are inflammation of 
the bone caused by the growth in it of the germ of 
tuberculosis. 

Questions 

1. What kind of food do bones require? What food 
material contains a great deal of bone-building food? 

2. What special food should a mother, who is nursing 
a baby, eat? Why? 

3. What is rickets? What is necessary to correct such 
a condition? 

4. What is the cause of bow-legs ? How is such a con- 
dition prevented? 

5. When is a bone dislocated? How may it occur? 
How should it be treated? 

6. What is a sprain? What is the treatment? What 
is the advantage of having a physician properly strap 
and bandage a badly sprained joint? 

7. What is a fracture? What precaution -is necessary 
to keep from injuring blood vessels and nerves? 

8. How does a fracture heal? 

9. What are the causes of stooped shoulders? How 
can one avoid being stooped? 

10. What are the disadvantages of stooped shoulders? 

11. How should one breathe to develop an erect figure 
and supply pure air for the body? 

12. What is a bone felon? What is the cause of it? 
What is the best treatment? What is the purpose of such 
treatment ? 

13. What is white swelling ? 

14. What is Pott's disease of the spine? 



CHAPTER VIII 



THE MUSCULAR SYSTEM 

Power of Locomotion. One remarkable difference be- 
tween animals and plants is the power of the former to 
move them- 
selves about, 
or the power 
of 1 o c o m o- 
t i o n. A tree 
when planted 
must remain 
in the same 
spot for years 
its only move- 
ment being 
from its 
power to 
grow larger 
and taller. 

An animal 
m a y change 
its location 
of its own 
accord many 
times daily 
or move parts 
of itself 
thousands of 
times. This 
power of ani- 
mals to move is furnished by its muscles. 

57 




Fig 



21.— Some of the muscles of the back and 
neck. 



58 PHYSIOLOGY, HYGIENE AND SANITATION 



The lean or red meat of animals is its muscles. When 
such meat is thoroughly boiled it may be torn into strings 
or shreds which are called fibers. These fibers are 
joined together by connective tissue which unites at the 
end to form the tendon. 

Connective Tissue. This is a name applied to the in- 
elastic tissue which is used for binding every part of 
the body together. It is found everywhere in the body 

and so finely does 
it penetrate it that 
if by magic, the 
bones, muscles and 
all of the other 
tissues could be 
withdrawn leav- 
ing connective tis- 
sue alone there 
would be left a 
perfect mould for 
every muscle, bone 
and organ. A scar, 
after an injury to 
the soft part of the 
body, is a collec- 
tion of connective 
tissue cells that na- 
ture has used to 
fill up the gap. The 
stiffness in a joint after rheumatism is caused by the 
growth of this tissue in the parts which were inflamed. 
It is one of the supporting tissues of the body and is 
found most abundant in all the tendons, ligaments, and 
sheaths of the body which are used to bind the various 
parts together. 




Fie 



22.- 



-Showing- some of the muscles of 
the head and face. 



THE MUSCULAR SYSTEM 



59 



The Muscles and Their Functions. There are more than 
five hundred muscles in the body making up about one- 
third of the weight 
of the body. There 
are many shapes of 
muscles to serve 
their various pur- 
poses. The chief 
function of muscles 
is to produce mo- 
tion. 

Many muscles are 
used in standing or 
walking, writing, or 
talking. It is by ac- 
tion of muscles that 
blood is pumped 
through the body or 
that air is breathed 
into the lungs. A 
second value of the 
muscles is . to help 
protect the delicate 
organs. Large blood 
vessels are usually 
protected by a deep 
covering of muscles, 
and the stomach, 
liver, kidneys and 
intestines are in- 
closed in a cavity which is protected largely by strong 
muscles. Thus they aid the bones in protecting delicate 
organs. 




Fig-. 



23.— (Voluntary) muscles 
shoulder and arm. 



of the 



60 PHYSIOLOGY, HYGIENE AND SANITATION 



A third use of the muscles is to help support the skele- 
ton or framework by binding its joints together. Mus- 
cles which move the limbs, back, and perform all the 

movements under 
our control are fas- 
tened to the bones 
and pass over the 
joints. Thus they 
stiffen the bonework 
and help tendons 
and ligaments t o 
hold the skeleton in 
shape. 

In the voluntary 
muscles, the muscle 
fibers are very much 
longer than in the 
involuntary muscles. 
We can control many 
muscles at will. 
These are the vol- 
untary muscles. 
Should we desire to 
stand or run or 
throw a ball, the vol- 
untary muscles re- 
quired to do this 
would obey our com- 
mand. If we should 
command our heart 
to stop its beating, it 
would work just the 
same. It is an involuntary muscle or one over which the 
will has no control. Some muscles are partly voluntary 




Fig-. 



24.— Muscles of the chest and 
abdomen. 



THE MUSCULAR SYSTEM 61 

and involuntary. We may stop breathing for a short 
time but in spite of our efforts the muscles will go to 
work and draw in the air to purify the blood. These 
muscles, like those which cause the eye to close, are both 
voluntary and involuntary. 

Muscular Sense. We form our judgment of the weight 
of things by the strength of the muscles required to move 
them. This muscular sense can be cultivated to a re- 
markable degree. Grocers can tell by the "feel" of an 
article about how much it will weigh. We lift a glass 
of water confident of not spilling it or appearing awk- 
ward, for the muscles of the arm have been trained by 
handling objects of that weight. If the glass were filled 
with mercury (quicksilver) and the person thought it 
was filled with water, the muscles would act very awk- 
wardly because of its greater weight until they become 
used to the new task. One would not attempt to pick up 
a toothpick in the same way as he would to pick up a 
bar of iron. The muscles, trained to their tasks, would 
prepare themselves almost without our knowledge for the 
greater effort. We use this muscular sense a great many 
times every day in standing, walking, running, throwing 
and in every voluntary movement we make. The mus- 
cles are balanced and trained to act smoothly and grace- 
fully because of a trained muscular sense. 

Attachment of Muscles. Muscles do their work by con- 
tracting, or becoming shorter and thicker. If salt be 
sprinkled upon the skinned leg of a frog, recently killed, 
the muscles will be seen to contract as if the animal were 
alive. When the elbow is bent in raising the forearm the 
large muscle (biceps) of the arm contracts and the ends 
of the muscle come closer together. Its power would be 
lost if each end were not fastened. The places where 



62 PHYSIOLOGY, HYGIENE AND SANITATION 



muscles are fastened are called points of attachment. The 
most fixed point, or the place a muscle pulls from, is its 
origin. The most movable end is its insertion. The 

origin and insertion of all 
the voluntary muscles are 
points usually on the skele- 
ton. The biceps like nearly 
all of the muscles of its 
kind is larger towards the 
middle and tapers down 
to a firm, hard, slender 
band. This band is the 
tendon or "leader" as it 
is often called. "Who has 
not pulled the "leaders" 
of a chicken or turkey's 
foot to make the toes bend 
and straighten ? These 
strong cords are made up 
of the connective tissue 
which bind the muscle 
fibers together, and keep 
the part near the joint 
from being large and 
clumsy. 

The tendons pass over 
the joints occupying very 
little space, and are at- 
tached firmly to the per- 
iosteum and the bone. The bones at the joint are made 
larger, as we learned previously, so that the muscle in 
contracting may lose none of its force in pulling the 
joints closer together. 




Fig-. 25. —Muscles of the lower leg- 
and foot. 



THE MUSCULAR SYSTEM 63 

Arrangement of Muscles. Muscles are usually ar- 
ranged in pairs and oppose one another. Thus the biceps 
bends the arm at the elbow and its opponent, the triceps, 
straightens it. One muscle will close the eyelid and an- 
other open it; muscles pull the foot forward while their 
opponents will draw it back. 

Muscles at rest evenly balance one another yet there is 
just a little pull of each all the time. This is proven 
when a tendon is cut through. A gap will appear be- 
tween the cut ends and a great deal of usefulness of that 
muscle may be lost if the ends do not grow together. 
A young lady once accidently cut the tendon of the mus- 
cle which raised the little finger. Her career in music 
was stopped because the tendon did not grow together 
again and that finger could not be lifted from the keys 
quick enough to perform well upon the piano. 

Training of Muscles. Babies have very little control 
of their muscles. After a few months the muscles have 
been taught to reach out and grasp things, to move the 
legs and arms in crawling, and finally to stand alone and 
walk. The muscles which control the voice, at first could 
only produce the cry of babies. After much training 
they begin to use the organs of speech, to say a few 
words and gradually learn to talk. 

After a few years the muscles may be trained to do 
very difficult and wonderful things • to throw a ball ac- 
curately, to write rapidly and plainly, to plow, to play 
a piano, violin or other musical instruments, to sing, to 
operate a typewriter, to do skilled work in the factory, 
to perform delicate surgical operations, and a great many 
other things which are seen and done so often that we 
seldom appreciate the wonderful work which the body 
as a machine performs. 



64 PHYSIOLOGY, HYGIENE AND SANITATION 



Muscle Wear and Repair. The muscle cells like other 
parts of the body are being worn out every hour of the 

day. In health these dead cells 
are renewed promptly and the 
muscles are as good and even 
stronger than before. Every 
time we walk, run, or move 
there is damage done to the 
muscle cells ; but the loss of 
these cells only adds to our 
health if we know how to live 
so the worn out cells are re- 
placed by new and better ones. 
The muscle by exercise becomes 
redder, firmer and stronger. 
Feel the arm of a small child 
and see how flabby it is; then 
feel the arm of one who does 
hard labor or who exercises 
his muscles a great deal and 
see how hard the muscles feel 
and how strong they are. Such 
a person is in a position to en- 
joy the best of health if he 
obeys other laws of health as 
well, does not drink liquors, or 
lead a dissolute life or in other ways weaken and poison 
his body. 




Fig 



26.— Muscles of the 
thigh 



THE MUSCULAR SYSTEM 65 

Summary 

The distinguishing difference of animals and plants 
is the power of locomotion of the former by means of 
muscles, 

Muscles are the "lean meat" of an animal and are 
made up of bundles of fibers bound together by connec- 
tive tissues. 

Connective tissue is one of the supporting tissues of 
the body and is found throughout its structure. 

The muscles number about five hundred and are of va- 
rious shapes to serve various purposes. Muscles have the 
three main uses of producing motion, protecting delicate 
organs, and supporting the skeleton and giving shape to 
the body. 

Muscles are made up of cells which are bound together 
by connective tissue into bundles of cells or fibers. 

A tendon is a collection into one cord of all the bands 
of connective tissue which binds the bundles of fibers of 
a muscle together. 

Muscles are either voluntary or involuntary, depending 
upon the ability of the will to operate them. 

A muscular sense is the result of training the muscles 
to act promptly and certainly when performing the 
many operations of our body. 

Muscles produce motion by their power of contrac- 
tility, acting from the point of origin upon their point of 
insertion. The tendons of voluntary muscles pass over 
the joints of the skeleton and are fastened firmly to the 
bone of the part to be moved. 

Muscles usually act in pairs, one opposing the other. 

Tendons enable muscles to transfer their power past 
a joint without increasing its size. 

Phy.— 3 



66 PHYSIOLOGY, HYGIENE AND SANITATION 

Muscles in infancy work very imperfectly but become 
trained and expert in their work with advancing years. 

The cells of muscles are worn out with use but in 
health are replaced at once with new ones and become 
stronger than before. The muscles of one who uses them 
a great deal, a farmer, blacksmith, or an athlete, are 
hard, red, and strong because of their use. The muscles 
of one who uses them little are pale, flabby and weak be- 
cause they have not been used enough. 

Questions 

1. What is meant by locomotion as applied to an ani- 
mal? 

2. What is "lean meat"? Of what is it composed? 

3. What is connective tissue? Where is it found? 
What are its functions? 

4. What is a "scar"? Why does rheumatism some- 
times make one's joints stiff? 

5. How many muscles are there? 

6. How many chief functions have the muscles? Name 
them. 

■ 7. Give six illustrations of the use of the body to pro- 
duce motion. 

8. Name three examples of the use of muscles to pro- 
tect delicate organs. 

9. Give the structure of a muscle. 

10. What are voluntary and involuntary muscles? Give 
examples of each. 

11/ What is meant by muscular sense? Give some illus- 
trations of the use of muscular sense ? What is meant by 
a person being awkward? 

12. How do muscles move the body? Why are both 
ends fastened? 



THE MUSCULAR SYSTEM 67 

13. What is the origin of a muscle? Insertion? 

14. What is a "leader"? Of what is it composed? 
What is the use of a tendon? 

15. How are muscles arranged to do their work? Why 
are they arranged thus? How is it known that muscles 
"pull" against one another? 

16. At what time in life are muscles untrained? What 
is meant by training muscles? Give ten illustrations of 
the work of trained muscles. 

17. How do muscles wear out ? How are they repaired ? 
What strengthens a muscle? Name three ways muscles 
may be weakened. 

18. What is the difference between the muscles of one 
who uses them a great deal and one who does not? Other 
things being equal, which will have the best health and 
accomplish more? 



CHAPTER IX 



HYGIENE OF THE MUSCULAR SYSTEM 



Exercise. Muscles grow in strength by exercise. A 
much used muscle is a strong muscle. It is larger, firmer 
and redder than an unused muscle. The 
lean meat of a hen's breast is the mus- 
cles of flight, and because she flies very 
little the breast meat is pale or white. 
The breast of a pigeon or wild duck or 
guinea is dark in color and much firmer 
because of the exercise of those muscles 
in flight. 

Exercise is helpful because the action 

of the muscles causes the blood to flow 

freely and makes us breathe more air 

into the lungs ; the body cells take on new 

life and new force is given to all the 

Fig- 27 —An ath- or g ans of the body ; our appetite for food 

is^niy^art^f * s i ncrease <l an( l its digestion is better; 

training s c * e a tired brain becomes rested and will 

think more clearly. 
Forms of Exercise. Walking is the most usual form of 
exercise. It brings into action the muscles of the limbs 
and back and the muscles of the abdomen. It is not suffi- 
cient because only certain groups of muscles are used. 
Running is a more violent form of exercise than walking 
and brings more muscles into play and, when used in 
moderation, is one of the most useful forms of exercise. 
Long endurance races work a great hardship on the 
heart muscle and do harm to the body instead of good. 

68 




HYGIENE OF THE MUSCULAR SYSTEM 69 

One should stop any kind of exercise when there is a 
feeling of faintness or undue fatigue. 

Jumping and Skipping are excellent if not indulged in 
too long. The muscles of the lower limbs, abdomen, back 
and arms are used in these exercises. 

Horseback Riding is very beneficial because many 
muscles are brought into action and the pleasure of the 
ride adds to the benefit from the exercise of the muscles. 

Exercise of Occupation. Farming. The person work- 
ing on a farm gets many forms of exercise that tend to 
develop all of the muscles uniformly. Plowing exercises 
every muscle of the body. Hauling, gifting, chopping, 
mowing, cultivating, and the many other forms of work 
on the farm make it the most favorable life for making 
strong, healthy men and women. 

Fortunate is the student who was raised upon a farm 
and used to outdoor life and work for, everything else 
being equal, he will be the winner in the race of life 
over the one who has led a life indoors. 

Games. Baseball, basketball, tennis, golf, football 
are all games which require a great amount of muscular 
effort and are splendid forms of exercise. 

When to Exercise. Those who lead the life of a stud- 
ent or a sedentary life should have a regular time each 
day to exercise ; before breakfast, an hour before meals, 
and light exercise before retiring. Violent exercise 
should not be indulged in immediately after a meal be- 
cause it causes the blood to flow away from the organs 
of digestion where it is needed to digest the food. 

Muscle Enemies. Too little exercise will cause weak 
muscles. The body will not receive enough fresh air, 
food will not be relished or digested so well. The poisons 
of the body will not be thrown off by the skin, kidneys, 



70 PHYSIOLOGY, HYGIENE AND SANITATION 

or bowels ; the blood will fail to repair the body cells so 
well and the brain will work slower. All these bad condi- 
tions will impair the usefulness of a person and finally 
make one ill or shorten his life. 

There is a direct relation between muscular exercise 
and brain efficiency; the brain workers will do their 
work best and longest with less fatigue when they exer- 
cise freely and properly. 

Tobacco and Alcohol. These poisons make muscle cells 
weaker and hinder their repair. The heart muscle is so 
affected by the use of tobacco that after a few months 
or years it fails to beat regularly and often flutters as if 
it would stop. This makes a condition known as a "to- 
bacco heart.' ' The body muscles at work become tired 
quicker than muscles which have not been poisoned by 
these drugs. In severe sickness when all the strength of 
the body is needed to win the fight, the person who is not 
addicted to the use of tobacco or alcohol is most likely to 
recover. In pneumonia and typhoid fever, where all the 
strength of the body is needed to get well, the death rate 
of persons who have poisoned their body with alcohol or 
tobacco is much higher than in people whose muscles and 
body are free from their effects. Trainers and athletes 
know this is true and prohibit the use of tobacco and al- 
cohol, when a team is training for a contest where pro- 
longed muscular effort and strong bodies are needed to 
win. 

An Erect Figure. The erect position of the body is 
kept by the action of the muscles along the spinal column. 
A stooping position results in a pressure upon the lungs 
and heart because the bones are not supported by the 
muscles in their natural position. If a stooped position 
is continued throughout childhood, the muscles will grow 
to fit a bent body instead of a straight one, and such a 



HYGIENE OF THE MUSCULAR SYSTEM 71 

person will be more or less deformed throughout his 
lifetime. In early years of life one should learn to hold 
the body erect when sitting, standing, or walking. This 
is done by stiffening the muscles along the entire back 
so that the spinal column will take on its graceful curves. 
The head should be thrown back and the shoulders will 
naturally take their proper place. It is a mistake to 
think that by simply pulling the shoulders back one 
assumes an erect position. After a few weeks of training 
a person can form the habit of keeping the body erect. 

Summary 

Muscles develop by exercise, becoming tougher, red- 
der and stronger. 

Exercise is a cell builder for the whole body because 
more air is supplied to it, more food is eaten and di- 
gested better, and poisons of the body are thrown off 
more easily. 

Walking, running, outdoor games, horseback riding, 
and certain occupations that require muscular effort are 
the best forms of exercise. 

Persons living indoor lives should take a certain 
amount of exercise each day in order to keep the body 
in health. 

Too little exercise will result in ill health, reduced 
efficiency or a shorter life and less enjoyment. The best 
brain workers and the most efficient men are those who 
keep their bodies healthy by exercise. 

Tobacco and alcohol are muscle enemies because they 
poison muscle cells and all the other body cells and make 
them weaker. This is shown by a larger number of peo- 



72 PHYSIOLOGY, HYGIENE AND SANITATION 

pie dying from dangerous diseases who have been users 
of tobacco and alcohol. 

An erect position can only be had by forming the habit 
of straightening the spinal column when sitting, standing, 
or walking. 

Questions 

1. What is meant by muscular exercise? What effect 
does it have on muscles ? Why is the meat of some ani- 
mals white or pale? Why red and dark? 

2. State seven reasons as to why exercise is helpful. 

3. Name ten common forms of exercise of children and 
adults. 

4. Why is walking not sufficient exercise? Is run- 
ning or jumping better? Why? 

5. Why are horseback riding, tennis, baseball, football, 
and golf fine exercise for muscles? 

6. What is better exercise than that of farm work? 
Why? Name four other occupations you know about 
which furnish plenty of muscular exercise. 

7. What is the advantage of a splendid muscular de- 
velopment over a poorly developed muscular system? 
Why? 

8. Do people who have strong muscles necessarily have 
great brain power ? Why ? What is the advantage, then, 
of having plenty of exercise? 

9. Name three muscle enemies. Why is too little exer- 
cise injurious? Give five reasons. 

10. How do tobacco and alcohol affect muscle cells? Do 
they affect body cells? How? What happens often to 
the heart muscle after use of these poisons? 



HYGIENE OF THE MUSCULAR SYSTEM 73 

11. Why do chronic drinkers and tobacco users die 
more frequently from typhoid fever and pneumonia or 
other dangerous diseases than those who do not use them? 

12. Are drinkers of whiskey, beer, or other alcoholics 
and users of tobacco chosen for athletic events? Why? 

13. How is an erect figure maintained? Why do some 
people have stooped-shoulders all their lives? Why is it 
necessary to train the body in an erect position in child- 
hood? 



CHAPTER X 
THE DIGESTIVE SYSTEM 

In the preceding chapters we have studied the frame- 
work of the body; its muscles, its power to move, re- 
pair itself, to fight its battles, and many of its operations. 
The question naturally arises, what produces all this 
power? 

Any machine to do things must have force and energy. 
A clock runs because of the force of its spring or weights. 
An automobile engine pulls its weight because of the 
power in its steam or in the explosions of gas within 
the cylinders ; a steam engine draws its immense burdens 
because of the energy stored up in coal which when 
burned under the boiler containing water, produces 
steam; a horse is powerful because of the energy which 
it receives from hay, oats, corn, or other food; and 
the human body to do all its work must be supplied with 
energy or force. This it receives from the food. The 
method of changing food into skin, bones, muscles, blood, 
brain, fat, etc., is one of the most interesting and won- 
derful things in all the world. 

Today on the dining table will be bread, meat, milk, 
and vegetables; tomorrow these will be changed into a 
blood cell, bone cell, brain cell, or some other part of 
the body, and its force will be used to walk, work, write, 
play, sing, produce beautiful music, or think, to bat an 
eye, swim, take a delicate stitch, or lift a heavy burden, 
and presently we shall be hungry again for food to sup- 
ply energy for other tasks. 

This change of food into flesh is the result of chem- 
ical actjion. 

74 



THE DIGESTIVE SYSTEM 75 

Chemistry. To have a practical knowledge of the 
kind of food to eat, its preparation and quantity, it is 
necessary to know something of the composition of mat- 
ter or the materials which make up the world. Chem- 
istry is the science which investigates the composition 
of all substances together with the changes resulting 
from their action upon one another under the influence 
of chemical force. 

Light* a match and watch the wood burn; the wood 
burns because of the chemical action of the oxygen of 
the air upon the wood which was once a part of a living 
plant. Coal burns because of the action of oxygen upon 
the carbon of the coal. The heat is thrown off because 
of this violent chemical action. Smoke is part of the 
substance which has not been consumed by the oxygen. 

Mix a teaspoonful of soda and vinegar together; 
notice how it boils (effervesces) and becomes warmer. 
This is because of the chemical action of the two sub- 
stances upon one another. Whenever chemical action 
occurs, heat is produced. 

Composition of Matter. Everything of the earth, 
living or dead, animal, vegetable, or mineral, is com- 
posed of about eighty things called elements. Think of 
taking only eighty substances and making hills, the 
rivers and oceans, the air, the trees, flowers, cities, rail- 
roads, the people of all the earth and its millions of ani- 
mals and plants, everything which we see, feel, hear, 
taste or smell. What a wonderful architect is God, 
who did it all! 

When two or more of .these elements unite with one 
another they form a chemical compound and may be en- 
tirely different in appearance, form or nature from the 
elements composing it. Two parts of hydrogen (a gas) 



76 PHYSIOLOGY, HYGIENE AND SANITATION 

and one part of oxygen (a gas) form water, the most 
abundant of all chemical compounds. When one part of 
carbon (a solid) is united with two parts of oxygen 
there is formed carbon dioxide, which is a gas. Every 
flame is giving off quantities of this gas. Animals which 
breathe air into their lungs, throw out of their lungs, 
with each breath, quantities of this carbon dioxide which 
has been formed in the body by chemical action. 

The most used elements in the making of all things 
are carbon, oxygen, hydrogen, nitrogen, sulphur, phos- 
phorus, iron, copper, silver, gold, lead, zinc, chlorine, 
sodium, potassium, platinum. 

The air which we breathe is not a chemical compound 
but is chiefly a mixture of two gases; oxygen, one part, 
and nitrogen, about four parts. These two gases do not 
unite with one another very well because they have very 
little attraction for each other. In chemistry this at- 
traction is called affinity. We breath air to get this life- 
giving oxygen into our blood so that it will produce a 
chemical action in our body cells. This chemical action 
produces the heat of our bodies and the poisonous car- 
bon dioxide which is formed in the body cells is thrown 
out of the body with our breath. 

Composition of Vegetable and Animal Matter. Liv- 
ing things like trees, grasses, vegetables, people, horses, 
fish, birds, etc., are the most complicated of all created 
things. The elements composing them are combined into 
many different chemical compounds. A very few chem- 
ical elements, however, make up these tissues. Car- 
bon, oxygen, hydrogen, nitrogen, sulphur, and phos- 
phorous make up most of the tissues of living things. 

We have learned that body cells are being worn out 
all the time and new ones in health take their places. 



THE DIGESTIVE SYSTEM 77 

A body cell contains these elements of carbon, hydro- 
gen, nitrogen, oxygen, sulphur, and phosphorous, as do 
the vegetables, meats, and other foods we eat. "When 
food is digested or acted upon chemically in our organs 
of digestion, it is ready to be taken up by the blood and 
carried to every body cell that needs a new cell 
or requires more energy and power. When food reaches 
worn out body cells or weakened ones the oxygen which 
we get by breathing air into our lungs and which is car- 
ried also in the blood causes a chemical change to take 
place between the body cells and the digested food. New 
cells are made and new force is created as a result of 
these chemical changes which are going on all the time 
in our bodies and enough heat is created to keep our 
bodies warm. A dead animal gets cold because chemi- 
cal action in the body cells has stopped. 

Life by Death. We are in a position now to under- 
stand that we live by death. In living creatures around 
us, cattle, sheep, poultry, fish, and in living plants like 
corn, wheat, bats, vegetables, there are the necessary 
chemical elements of carbon, hydrogen, nitrogen, oxygen, 
sulphur, phosporous and others needed for building up 
our bodies. We destroy these living things, and after 
preparing them they are put into our bodies which 
change them into a suitable form for the blood to carry 
to starved or worn-out body cells. New cells are formed 
by chemical action and new life and strength are given 
to our bodies. 

Summary 

In performing its various operations, the body, like 
any other machine, must be supplied with force or en- 
ergy. This is received from the food we eat and air we 
breathe. 



78 PHYSIOLOGY, HYGIENE AND SANITATION 

The process of converting food into flesh, action, and 
thought, is a most wonderful one and depends upon 
chemical action. 

Chemistry embraces the study of the composition of 
matter and the changes resulting from the action of 
parts of matter upon one another under the influence of 
chemical force. 

The burning of wood, coal, or other substances is a 
chemical action of the oxygen of the air upon the car- 
bon of such materials. 

All matter is composed of elements numbering about 
eighty. Water is a union of two parts of hydrogen and 
one part of oxygen. Union of chemical elements as a 
result of chemical force to form new substances forms a 
chemical compound. A mixture is not a chemical com- 
pound; Air is a mixture, largely, of one part oxygen 
and about four parts nitrogen. Carbon, oxygen, hydro- 
gen, nitrogen, sulphur, phosphorous, iron, copper, silver, 
gold, lead, zinc, chlorine, sodium, potassium, are the most 
commonly found elements in nature. 

The cells of the human body are composed mostly of 
carbon, oxygen, hydrogen, nitrogen, sulphur and phos- 
phorous. These elements are found in the food we eat, 
and by chemical action are changed into new cells, 
thereby giving to the body its heat and energy. 

This chemical action in the body cells is brought 
about by the oxygen in the air which is carried by the 
blood to every body cell. 

We live by death. The living plants and animals 
which are used for food when cooked and digested are 
converted into such chemical compounds that the carbon, 
oxygen, and the other elements in them are converted 
into new cells or furnish new energy to those that need it. 



THE DIGESTIVE SYSTEM 79 

Questions 

1. What is necessary to make a machine operate? 
Give five examples of machines and state their source 
of energy. 

2. What supplies the motive force of the human ma- 
chine ? Name several kinds of cells which receive energy 
from food. 

3. What is chemistry? What has it to do with a 
knowledge of the body? Give three examples of chem- 
ical action? What is water? What is air? What is 
smoke? What is a chemical compound? What is the 
difference between a mixture and a chemical compound's 

4. About how many elements have been discovered? 
What are elements? Name sixteen of the most com- 
monly found elements. What is chemical affinity? 

5. Of what elements are the cells of the body mainly 
composed? Why do we eat vegetables and meats? 

6. Why do we breathe air into the lungs? Why do 
we breathe air out of our lungs? 

7. What is the purpose of having oxygen in our blood? 

8. What carries digested food to the body cells? 
What else does that agent carry to them? 

9. What happens when a worn-out or tired body cell, 
some digested food and some oxygen meet anywhere 
in a living body? What happens to the cell? What be- 
comes of the food and the oxygen? Is there any rela- 
tion between what happens here and the burning of a 
match? Why? 

10. Why is the body warm when living? Why cold 
when dead? 

11. Explain what is meant by "living by death." 



CHAPTER XI 

THE ORGANS OF DIGESTION 

The process of digestion takes place within a tube 
about thirty feet long. This tube commences at the lips 
and extends through the mouth, esophagus, stomach, and 
is then coiled about in many folds in the abdomen where 




Fig-. 28.— The stomach. A. End of the food tube (esopha- 
gus) from the mouth. B. Opening- into the small 
intestines. 

it is called the intestines or bowels. The first twenty feet 
of this tube in the abdomen, is called the small intestines 
and the last six or eight feet, the large intestines. This 
entire tube is called the alimentary canal and is of vary- 
ing size. The first enlargement is in the mouth, then 
follows a narrow part, the esophagus, about ten inches 
long which expands into a pouch. This pouch when full 
is about twelve inches long and four inches in diameter 
in an adult and is called the stomach. It then passes 
through a narrow opening, the pylorus, into the small 

80 



THE ORGANS OF DIGESTION 



81 



intestine which is about an inch in diameter. The tube 
remains about the same size until it merges into the 
larger intestine. 

Into this tube are poured at different places a number 
of juices furnished by glands. These digestive juices act 
chemically on different kinds of food reducing them to a 
liquid, splitting them up into simpler compounds ready 
for absorption. 





;$$» , 








H >- 




sp-MJ}M 


^ 




Pi ' f 

mkfM 




W¥< 


$^s 


w 


mtk 


r § 


i£ ^St'^S^i 1 


£* 




ffr % 


9| 












wjr -|i If 

p»> j?s§||j§ 







Fig-. 29.— The intestines. 



The alimentary tract or tube is lined throughout with 
a delicate red membrane, the mucous membrane, and it 
is supplied with muscles in its wall so that the food is 
pushed along from place to place by the contraction of 
these muscles, one layer of which runs around the tube 



82 PHYSIOLOGY, HYGIENE AND SANITATION 

like a ring, and another lengthwise. In some parts, an- 
other layer runs slantingly or obliquely with the tube. 
When these muscles contract they force the food for- 
ward acting much after the manner in which a fishing 
worm (angle worm) travels. If a mass of food is swal- 
lowed, these muscles grasp it just when it has passed 
back of the throat and pull it downward whether we 
will or not. Clowns can drink water when standing on 
their heads for this reason. 





--' j& 




->"' - -'l -*M 






,-■.;•• - 1 






<$m ■?-' «* 




t^ jHRP"* 


'■'. ,•'' }'> J \^. 






,fr • 


§S ■■:--;! : f'-. r 


mm 








! 1 1 1 ¥ W 


* 




T^f^^^'^^^M^ /J st f ; : 1 rj 




■ ""11? 


l\\\ XK^^^t^i^' 






%. %. siT * 






'- J 






..Jim 






^ /p 






Jm ^^ 













Fig-. 30.— The teeth. One of the organs of digestion. 



Mastication. The teeth are very important organs of 
digestion. The muscles of the jaw by contracting cause 
the lower jaw to crush against the upper one, in both of 
which are set the teeth. The food is held between these 
grinding and crushing instruments by the muscles of 
the tongue and cheeks so that large masses of meat, 
bread, or other food are ground into fine particles. This 
process is called mastication. 



THE ORGANS OF DIGESTION 



83 



Insalivation. At the same time the teeth are at work 
there is being poured out of little tubes, which reach 
back to the salivary glands, a fluid which soaks all through 
the food and makes a pasty or soft mass out of it. It 
makes the food easier to swallow and by the action of 
the ptyalin which it contains, the starches are partly 
converted into a form of sugar. This process is called 
insalivation. 

The salivary glands are six in number; three on each 
side of the face. One is just in front and below the ear; 
this is the one which becomes 
enlarged and painful w T hen a 
person has mumps, and is 
known as the parotid. An- 
other, the sub-maxillary, is 
just below the border of the 
lower jaw and the third, the 
sub-lingual, is situated below 
the tongue. These glands man- 
ufacture from the blood the 
saliva which contains a fer- 
ment to convert starches into 
a form of sugar. 

A ferment or enzyme is a substance which can cause 
by its presence a breaking up of certain chemical com- 
pounds into simpler ones and yet undergo no change it- 
self. 

Gastric Digestion. Arriving in the stomach the food 
is mixed with gastric juice which is secreted by the gas- 
tric glands in the stomach wall. This juice contains a 
ferment called pepsin which acts principally upon the 
proteids. It contains also hydrochloric acid which must 
be present for the action of the pepsin. 




Fig:. 31.— One of the sali- 
vary glands (the parotid). 



84 PHYSIOLOGY, HYGIENE AND SANITATION 

Intestinal Digestion. After the food has reached a 
proper degree of digestion in the stomach, one end of 
the stomach opens and the food passes into the small in- 
testines. Here it is mixed with the bile, and the pan- 
creatic juice which contain three active enzymes. One of 




Fig- 22 —The liver. A. and B. "lobes" of the liver. 
C. The tip of the gall-bladder. 

these digests the fat and the other two aid in digesting 
the starches and the proteids which have escaped the 
digestive action of the saliva and gastric juice. The bile 
is not an active digestive agent in itself but by its pres- 
ence aids the other juices to do their work. 

The bile is secreted by the liver which is the largest 
gland in the body and weighs nearly four pounds. Its 
cells manufacture the bile (gall) which is stored for use 
in the gall bladder. When the food reaches the intestines 
this bladder or pouch empties its contents through a 
tube into the small intestine. 

The pancreatic juice is secreted by a long, slender gland 



THE ORGANS OF DIGESTION 



85 



back of the stomach and finds its way to the small in- 
testine through a tube which joins the gall bladder tube. 

Absorption. Along the course of the small intestine 
are tiny projections of its lining mucous membrane giv- 
ing it a velvety appearance. These are called villi. These 
villi absorb or "soak up" the digested food so that it 
finds its way into the blood stream. All of this digested 
and absorbed food in the blood now passes through the 
liver and is finally 
prepared for use by 
the body cells. The 
liver is the great 
' i clearing house ' ' for 
all the food we eat. 
Poisonous substances 
are arrested here and 
an effort is made to 
oxidize them or con- 
vert them into harm- 
less substances. The 
liver of a person who 
drinks beer, whiskey, and other alcoholic beverages fre- 
quently becomes greatly enlarged because the liver has 
overworked itself to stop these poisons before they reach 
the body cells. If such a person persists in drinking 
these liquors the overworked liver undergoes a slow in- 
flammation and connective tissue takes the place of worn- 
out liver cells. This causes the liver to become smaller 
in size and knotty in appearance when it is called "hob- 
nailed" liver. Such a person suffers constantly from in- 
digestion and altogether has an unhappy existence. 

Assimilation. The process by which the food,, digested 



* V *'' ' 




^\ 




,JM 






~%l'y** 


' >/* > ' -'-'•-'""/ ; : 


%J ? ; 


r'^jS'' ' - r % \A/' ^ -' 


?% 


;'>V^ j? * 




f< :r r \:> ' ■ \ 




1W «• 


w^ 



Fig-. 33.— Cirrhosis of the liver ("hob- 
nailed" liver) from long-, continued 
use of alcoholic liquors. 



86 PHYSIOLOGY, HYGIENE AND SANITATION 

and absorbed into the blood stream, is converted into new 
cells or "flesh" is called assimilation. 

The food, now properly prepared, is carried to the 
hungry cells and each cell takes unto itself the particular 
kind of food needed for its growth or recreation. Thus, 
bone cells require certain salts as lime, potash, and muscle 
cells, forms of protein. 

Summary 

Digestion of food is performed within the alimentary 
tract which is a tube of varying size about thirty feet 
long. It is divided into the mouth, esophagus, stomach, 
small and large intestine. Digestive juices containing 
ferments or enzymes are poured into this tube at differ- 
ent places to digest certain kinds of foods. It is lined 
with mucous membrane and supplied with muscles which 
are used to move the food forward. 

The teeth perform a valuable service in digestion by 
reducing the food to fine particles so that the digestive 
juices may act upon them to better advantage. 

Saliva softens the food and, by the action of ptyalin, 
converts starch into malt sugar. 

The glands of the stomach-wall secrete gastric juice 
which contains pepsin and hydrochloric acid and digests 
principally the proteids. 

The pancreas secretes the pancreatic juice containing 
three enzymes which digest fats, proteids, and starches. 

The liver secretes bile and receives the blood after food 
has been absorbed by the villi of the intestines. It 
stands guard for the body cells and endeavors to stop 
poisonous materials before they can do harm to the 
body. 



THE ORGANS OF •DIGESTION 87 

The liver of a drinker of alcoholic beverages often be- 
comes enlarged because of the efforts of the liver to stop 
these poisons before they reach the body cells. Later, 
the liver often becomes "hob-nailed." 

Questions 

1. What is the alimentary canal? How long is it? 
"What are its divisions? What is its function? 

2. What is mastication? Where and how is it per- 
formed? What is its purpose? 

3. What is insalivation ? Name two. of its purposes. 
What is the saliva? What produces it? How many 
salivary glands have we? Where are they located? 

4. What is the esophagus? Into what does it empty? 

5. How large is the stomach ? Why is it made large ? 
What juice is secreted here? What secretes this juice? 
What does it contain? Why is hydrochloric acid pres- 
ent? 

6. What is a ferment ? Name two found in the body. 

7. Where is the pylorus? What does it do? 

8. What juices are found in the intestine? How many 
enzymes in the pancreatic juice ? What is their func- 
tion? 

9. Of what use is the bile? What secretes it? What is 
the gall bladder? What does it do? What is absorp- 
tion ? Assimilation ? 

10. How large is the liver ? What other important duty 
has the liver? What does alcohol often do to the liver? 
Why? What is a "hob-nailed" liver? 



CHAPTER XII 

KINDS AND QUANTITY OF POODS 

Classes of Foods. Every one's experience shows that 
many different kinds of foods are eaten in a life time, 
but examination shows that all such materials are com- 
posed of very few classes of food stuffs. They are usually 
divided as follows: 

1. Water. 

2. Carbohydrates. 

3. Fats. 

4. Proteids. 

5. Mineral Salts. 

Water is the most abundant of all materials entering 
into the formation of the body. It comprises about sev- 
enty per cent of the entire body weight and is the agent 
for liquefying and dissolving various ingredients of the 
food so that they may be absorbed into the blood stream 
for use by the body cells. It is found in all foods and 
tissues and fluids of the body and aids in ridding the 
body of poisons and wastes. 

The Carbohydrates include the starches and sugars. 
They contain carbon, hydrogen and oxygen but no nitro- 
gen. The hydrogen and oxygen are always so combined 
in the proportion to form water, i. e., two parts of hydro- 
gen to one of oxygen. 

Starches are found abundantly in plant life, chiefly in 
corn, oats, wheat, barley and other grains, and in pota- 
toes, peas and beans. Starch in the pure state is found 
in corn-starch. 

Sugars are of many kinds and include grape sugar, 

88 



KINDS AND QUANTITY OF FOODS 89 

cane sugar, beet sugar, maple sugar and malt sugar. 
Sugar is found in many fruits and is one of the most 
widely used and best of all foods. They are usually eas- 
ily digested and are more easily converted in the body 
into heat and muscular energy. Sugars may also be con- 
verted into fat in the body, and thus create a store-house 
of energy for use in extreme hunger during illness when 
the surplus and reserve energy of the body are needed 
to support it. 

Fats are found in abundance in both animal and vege- 
table life. Cotton seed, nuts and olives furnish much fat 
for use as food. Fats are found in varying quantities in 
the fat of animals, in milk, butter and lard. 

They contain carbon, hydrogen and oxygen but no 
nitrogen. The hydrogen and oxygen are combined in 
such proportion that they do not form water. Fats pro- 
duce much heat and energy when used as food and are 
more efficient in the production of energy than carbo- 
hydrates. In cold climates, fats and oils are largely 
used as food for this purpose. Persons who perform 
manual labor usually eat much fat because of the energy 
it produces in the body. 

Proteids. This class of food is absolutely needed to 
maintain animal life; however, this is not true of the 
sugar and fats. Proteids are found in animal and vege- 
table foods. They contain carbon, hydrogen, oxygen, 
nitrogen and, almost always, some sulphur and phos- 
phorus. 

The common foods, consisting largely of proteids, are 
milk and cheese, lean meat, eggs, peas, beans and lentils, 
oatmeal and wheat. 

Proteids are tissue builders more than heat and energy 
producers in the body. It is this class of foods that is 



90 PHYSIOLOGY, HYGIENE AND SANITATION 

used to build up new cells to take the place of those 
worn out and discarded. 

Mineral Salts. The bones, teeth and cartilages are the 
special tissues that require liberal portions of mineral 
salts for their formation and repair. The principal salts 
needed are sodium chloride or common salt, and the 
salts of lime or calcium. Salt is found in every tissue 
and fluid of the body, but more abundantly in the blood. 
Other salts needed are the phosphates, sulphates and 
carbonates of sodium and potassium and the phosphates 
and carbonates of magnesium. 

These salts are found in grains, vegetables, eggs, meat, 
milk and most of the staple foodstuffs of ordinary diets. 

Mixed Foods. Some foods contain all the different 
classes needed by the body but not in the right propor- 
tion. Thus it has been said, "Man can not live by bread 
alone." 

The following analysis of wheat reveals the truth of 
this statement: Wheat contains 13.6 per cent water, 
12.4 proteids, 1.4 fats, 67.9 starch, 2.5 cellulose and 1.8 
mineral salts. It is evident that one feeding upon such 
a food alone would soon die of thirst and certain parts 
of the body, as the bones and heat-producing cells, would 
suffer for the lack of the food elements necessary for 
their construction or repair. 

A mixed diet of bread, meat and milk would probably 
be ample for long periods of time for most people, for 
such foods contain a sufficient variety and quantity of 
materials to sustain life in all parts of the body. 

Milk has been called the " model food" for it contains 
in good proportions all classes of foods. Cow's milk 
contains about 3.5 per cent protein, 3.7 per cent butter 
(fat), 4.9 per cent lactose (sugar) and .7 per cent salts. 



KINDS AND QUANTITY OF FOODS 



91 



Preparation of Foods. Very few foods are eaten raw, 
among these being certain vegetables, fruits, milk and 
nuts. Most foods are considered unfit to eat unless they 
are properly cooked. There are three chief reasons for 
cooking foods: First, to develop a flavor. Who has not 
noticed the agreeable odor of a properly cooked steak, 
and been made hungry by its appetizing flavor? A raw 
beefsteak is repulsive to the sight and creates no desire 
for it as a food. Second, cooking makes it easier to 
digest foods, especially starchy foods. Oatmeal, pota- 
toes, beans and like foods should be thoroughly cooked 
to break their cells of starch so 
the digestive juices can reach 
it. Starch cells have tough en- 
veloping sacs which are soften- 
ed by cooking. A raw potato 
is almost impossible to digest, 
but when well baked, roasted 
or boiled the starch is freed 
from its cells and is quite eas- 
ily digested. Third, cooking removes all danger from 
infection by disease germs or parasites. Many vegetables 
are polluted in garden soil by flooding after rains, or by 
unclean methods of handling or marketing them. Meats 
are often contaminated by the foul hands of careless 
dealers. The germs or seed of typhoid fever, dysentery 
(flux) or tuberculosis may be deposited upon foods 
when improperly handled. Cooking effectively destroys 
such germs. 

Pork, beef and mutton sometimes contain small living 
worms or parasites. Pork especially should be thoroughly 
cooked, to avoid the danger from this source. 

Methods of Cooking. There are four methods of cook- 




Fig-. 



34.— Parasites in lean 
meat. 



92 PHYSIOLOGY, HYGIENE AND SANITATION 

ing: Boiling, baking, broiling and frying. Boiling is 
probably the most used and best method of cooking. If 
a soup or stew is desired, the juices of the meat or vege- 
tables must be set free into the water. For this reason 
the articles are placed into cold water and heated slowly. 
If the juices are to be kept in the articles and all the food 
values retained in them, they should be placed into boil- 
ing water. Vegetables should be cooked by placing them 
in boiling water. Meat placed in boiling water becomes 
coated over on the outside by coagulation of albuminous 
substances so that its juices can hardly escape and it 
may then simmer over the fire for a long enough time to 
become thoroughly "done." Baking is usually done in 
a hot oven; roasting, over a fire. In baking or "roast- 
ing" meats, the oven should be very hot in the begin- 
ning so that a coating is formed over the meat to hold 
the juices. 

Meat is improved in its flavor if, while baking, the 
juices are poured over it at intervals. Some excellent 
cooks sprinkle a thin coating of flour over such meat and 
the paste thus formed which turns to a good brown color, 
adding to the appearance, helps to keep the meat juices 
from escaping, thereby adding to the richness of flavor 
and food value. 

Broiling is a favorite method of cooking meats. It is 
done over a hot fire and the surfaces are at once coated 
over by the heat and the juices thus kept from escaping. 

Prying is a common method of cooking but not so 
desirable because foods cooked by this method usually 
become soaked with fats (grease or lard) and are harder 
to digest. When frying is to be done, the grease into 
which the foods are placed must be very hot to prevent 



KINDS AND QUANTITY OF FOODS 93 

the entrance of fat into the foods, and to retain the 
juices in them. 

Serving Foods. Much benefit may be had if foods after 
being properly cooked, are tastefully and properly 
served. A good beefsteak, brown biscuit and baked pota- 
toes served hot in clean, white dishes on a table covered 
with a linen cloth and "set" with glistening glasses and 
silver, create a greater relish for food and a happier mood 
for its enjoyment and digestion than the same food 
served cold in cracked plates on a table covered with 
"oilcloth" and tin cups. 

Summary 

"Water, carbohydrates, fats, proteids and mineral salts 
are the chemical classes of food. 

Water forms the greater part of the human body and 
is used as a solvent for foods for body cells. 

Carbohydrates consist mainly of the starches and sugars 
and are abundant in plant life. They are heat and 
energy makers for the body. 

Fats are heat and energy producers and are found as 
oils both in animal and vegetable life. 

Proteids are tissue builders and are found in large 
amounts in lean meats, beans, peas, cheese and milk. 

Mineral salts are needed for special tissues and to pro- 
mote assimilation. Common salt and lime salts are most 
abundant in the body. 

Mixed foods are needed to supply all classes of foods. 
Milk is an example of a mixed food. 

Foods are usually cooked to make them more easily 
digestible, to improve their flavor and to kill germs and 
parasites. There are four methods of cooking foods: 



94 PHYSIOLOGY, HYGIENE AND SANITATION 

Boiling, baking, broiling and frying. Meats used for 
making soups are cooked by placing in cold water. Bak- 
ing or roasting meats add to their flavor and food value. 
Food properly served is more appetizing and valuable 
as a food. 

Questions 

1. What is meant by chemical classification of foods? 
How many classes are there? Name them. 

2. What per cent of the body is water? 

3. Name four uses of water in the body? Where is 
water found in the body? 

4. What are carbohydrates? What is their chemical 
composition? 

5. Where are starches found? Sugars? 

6. What two uses have sugars and fats when eaten as 
food? 

7. What are fats? Where are they found? What is 
their chief function? 

8. Why are fats used for food in cold climates and by 
persons who do hard, manual labor? 

9. What is the chemical difference between carbohy- 
drates and fats? 

10. What are proteids? Name eight foods that con- 
tain liberal amounts of proteids? What is their special 
purpose as a food? Name four foods from animal life 
that supply proteids? Four from vegetable life? 

11. What three tissues require mineral salts? Name 
six mineral salts? Name the salts most needed in foods? 
Why? 

12. Why can not man "live by bread alone?" What 



KINDS AND QUANTITY OF FOODS 95 

combination of foods will probably sustain life longest? 
Why? 

13. Why is milk called a " model food?" What is the 
chemical composition of average cow's milk? 

14. What are raw foods? Name six foods sometimes 
eaten raw? Name three reasons for cooking food? How 
does cooking improve the flavor of food? 

15. Name five starchy foods that should be thoroughly 
cooked? Explain why? What are starch cells? 

16. How may foods become dangerous in spreading 
disease? What three diseases may be spread by careless 
handling of foods? What kind of food are subject to 
such dangers ? How can they be made safe for use ? 

17. What food sometimes contains parasites? What 
should be done with such foods? 

18. Name four methods of cooking? How should meat 
and vegetables be cooked for making stews or soups? 
Why? Why are vegetables always cooked by placing 
them in hot water? 

19. Why should meats be placed in a hot oven or over 
an open flame when "roasted" or broiled? What is the 
objection to "fried food?" Which can be digested more 
easily — fried or baked potatoes? Why? 

20. Explain the advantage of serving food properly? 
Make some suggestions to show how foods may be 
served ? 



CHAPTER XIII 

FOODS 

Food Values. Food is the fuel for the body. Next 
in importance to the selection of the kinds of food for 
the body's use, is the determination of the quantity of 
food to be used. This question involves not only the 
total amount of food and drink required each day, but 
the quantity of each class of food needed. A meal that 
supplies the proper quantity of sugars, fats, proteids, 
and mineral salts is said to be a balanced ration. 

The rule most of us follow is to eat when we are 
hungry and what appeals to our appetite. It is a fairly 
good one, but it leads to many errors. Frequently, too 
many pickles, too much candy, cake and other sweets 
are eaten merely because they taste good. This habit 
results often in impaired digestion and harm to the body. 
A meal of eggs, meat and beans contains too much pro- 
tein; one of bread, rice, potatoes and "hominy" con- 
tains far too much starch. A balanced ration is, there- 
fore, needed to supply the total quantity of food and 
of each class. 

. Food values are determined by a unit of measure, just 
as the value of United States money is determined by 
the dollar. This measure is called a calorie, and it 
equals the increase of heat in one pint of water when 
its temperature is raised 4° F. A boy of twelve requires 
about 1,200 of calories each day, a woman, 2,500, and a 
person who does hard labor, about 3,600 units each day. 
A healthy man usually eats about one-fourth of a pound 
of dry proteid food each day in addition to sugars and 
fats that are required to supply his body with energy. 

96 



FOODS 97 

Table of Food Values. The following table gives the 
quantity of food having a value of one hundred calories : 

Cooked or flaked breakfast foods % to 1*4 cups 

Milk % cup (whole) 

lYs cups (skim) 
Butter, olive oil or any kind of fat....l tablespoon 
Bread, 3 inches by 3% inches by 1 

inch 1 slice 

Fresh fruit: 

Large apple or orange 1 

Medium banana or bunch of grapes.. 1 

Medium peaches or pears 2 

Prunes, medium 4 or 5 

Raisins 25 

Figs iy 2 large 

Eggs 1 large 

Meat (beef, lamb, mutton, veal, 

chicken) 2 ounces (about) 

Bacon — small thin slices 4 

Sugar 2 tablespoons 

(scant) 

Potatoes 1 medium 

Macaroni and cheese y 2 cup 

Rice pudding % cup 

Ice cream made with thin cream y± cup 

Cornmeal 3 tablespoons 

Hickory nuts, chopped 1 tablespoon 

Hominy 2 tablespoons 

Honey 1 tablespoon 

Olives 7 or 8 

Peanut butter 1 tablespoon 

Peanuts, 1 cup, 777 calories 

Peas 1 cup 

Rice 2 tablespoons 

Baking powder biscuits ..2 small 

Graham crackers 2 

Doughnuts y 2 

Beans, baked 1/3 cup 

Lima, fresh y 2 cup 

Cabbage, dried y 8 . cup 

Cabbage, shredded 5 cups 

Cucumbers, 7 inches long 2 

Radishes, red button 3 dozen 

-., — _„ ^ 

A meal of wheat bread and milk weighing one pound 
contains about one thousand fuel units of food, or 
calories. 



Phy.- 



98 PHYSIOLOGY, HYGIENE AND SANITATION 

In selecting the articles of food for a meal not only 
the various classes of food must be included, but the food 
value of each article should be considered, and the total 
value in calories or food values furnished. 

The above table of food values is useful to assist one 
in choosing a balanced ration from the standpoint of 
economy. Cheese and peanut butter have a high pro- 
teid value and are usually much cheaper than meats 
chosen to supply this class of food. A careful study of 
food values in relation to the market price affords a 
good opportunity to save money which otherwise may 
be wasted upon foods which do not have so high a food 
value. 

Alcohol is injurious to the digestive organs. When 
as much as five per cent of the contents of the stomach 
is alcohol, it hinders the work of the gastric juice. Its 
presence in an empty stomach causes a redness or con- 
gestion of its lining or mucous membrane, and repeated 
ingestions of alcohol cause a destruction of tissue cells 
with resulting inefficiency and forms of indigestion. 

Its effects upon the liver when its use is continued are 
marked. The liver becomes enlarged and its ability to 
make bile and exercise its function of preparing food for 
assimilation is lessened. 

How to Eat. Foods should be eaten at regular periods, 
with an interval of five to six hours, during which time 
the stomach and bowels may complete the digestion and 
absorption of the preceding meal and rest. Solid foods 
should be chew T ed thoroughly and well mixed with saliva 
before swallowing. 

Digestion is a complex chemical operation and any 
interference with it before its completion may result in 
indigestion or faulty digestion. For this reason, candy, 



FOODS 99 

cakes or other foods should not be eaten between meals. 
Rest for the stomach is as important as rest for the 
muscles or brain, and too rapid or too frequent eating 
or over-eating will result in impaired digestion. 

The meal hour should be the happiest period of the 
day. Good humor, pleasing conversation and freedom 
from worry or care, promote the secretion of all the 
digestive juices and thus aid digestion. Worry, fatigue, 
either mental or physical, sorrow or temper, is a hind- 
rance to the enjoyment and digestion of food. 

Loss of Appetite often is caused by too frequent eat- 
ing or eating too much food or improper kinds of food. 
Pickles, spices and sweets are often used to stimulate 
a poor appetite and this leads to further disturbances. 
Alcohol in beer, wine or whiskey is spoken of sometimes 
as "appetizers." They should not be used for they 
create a false desire for food and over-eating with its 
train of troubles follows. 

Patent medicines, many of them containing alcohol 
or other dangerous drug, are often used by credulous 
people to relieve indigestion or "stomach trouble." They 
usually do harm and may lead to the formation of a 
drug habit. 

Summary 

The body which makes heat, energy, new tissues and 
repairs itself needs fuel or food. It needs not only cer- 
tain kinds of fuel but sufficient amounts of each class 
of food. Such a meal is a balanced ration, and the whole 
meal should have a total food value to furnish enough 
heat and energy but no more. Food values are deter- 
mined by a unit of measure, called a calorie. A boy of 



100 PHYSIOLOGY, HYGIENE AND SANITATION 

twelve requires about half the number of calories in a 
meal as a woman, while a laboring man requires three 
times as much as a boy. 

The food value of any meal may be measured by 
knowing the amount of the various foods used in the 
preparation of the meal and the quantity of each food 
used having a food value of one-hundred calories. For 
example, four small thin slices of bacon, a piece of bread 
three inches long, three and one-half inches wide and 
one inch thick, and one egg would make a meal having 
a food value of three hundred calories. (See table.) 

Many foods having a high caloric value are much 
cheaper in price and can furnish the body with as much 
power and heat as other foods which sell for a much 
higher price. 

Alcohol is injurious to the digestive organs. It inter- 
feres with the action of the gastric juice in five per cent 
dilutions. After continued and prolonged use it does a 
permanent damage to the liver and frequently produces 
a " hob-nailed " liver. 

Questions 

1. Why can food for the body be compared to fuel 
for an engine? Can too much "fuel" be fed to the 
human body? How do you know this? 

2. "What is a balanced meal? What else is it called? 

3. What makes us eat what and when we do? Is it 
a good rule to follow? Why? 

4. Give an example of a meal with too many starches? 
Think of another one, Give two examples of a meal 
with too much protein. 

5. Explain what is meant by a calorie? If a quart of 



FOODS 101 

water at sixty-eight degrees F. is heated to seventy-six 
degrees F., how many calories were needed to do this? 

6. How many calories each meal does a boy of twelve 
need if he eats only three times a day? How many 
calories would be needed by his mother if she did not 
perform hard manual labor? By his father if he were 
doing hard manual work? 

7. If a man eat one-fourth of a pound of steak, drinks 
nearly three cups of milk and eats three slices of bread, 
each three inches long, three and one-half inches wide 
and one inch thick, how many calories would be repre- 
sented in such a meal? Explain. (See table.) 

8. Name four foods that can be used to make a bal- 
anced ration for a house wife, and show how many calor- 
ies it would contain to furnish her with the necessary 
heat and energy. 

9. Prepare a menu, or list of foods, for a breakfast for 
a working man, giving the kinds and amounts of each 
food needed for a balanced ration. Prepare such a menu 
for a luncheon or " dinner.' ' A supper. 

10. Prepare a menu for supper for a family of five, a 
mother, the father, two boys, aged ten and twelve, and 
a girl of eight? What is the total caloric value of the 
meal? How much of each food must each member of 
the family eat to furnish the necessary caloric value to 
supply the body's needs? (See table.) 

11. Which is the cheaper for food values, one and 
one-half pounds of steak at thirty cents a pound or one 
dozen eggs at thirty-five cents a dozen? Why? 

12. How does alcohol injure digestion? 

13. What is its effect on the lining of the stomach 
when used as a beverage? 



102 PHYSIOLOGY, HYGIENE AND SANITATION 

14. What is its effect upon the liver after continued 
use? 

15. Give two general rules for eating? 

16. Why may eating between meals be harmful? 

17. What effect has the state of mind during meals 
on digestion? 

18. Give three reasons for loss of appetite? Should 
alcohol be used in any form to stimulate the appetite? 
Why? 

19. Should patent medicines be used for stomach 
troubles? Why? 



CHAPTER XIV 

PRESERVATION OF FOODS 

At certain seasons of the year many foods are abundant 
and cheap and unless some means are employed to store, 
preserve and keep them, they are wasted. This is true of 
green vegetables, berries, apples, peaches, grapes, pears 
and like fruits, eggs and poultry. 

Green or "string" beans, corn, peas, tomatoes, berries 
and beets may be "canned" for winter use by simple steri- 
lization. Such food after being prepared, as for immediate 
use, are packed in tin or glass jars which are then filled 
with water to which one teaspoonful of common salt is 
added to each quart, and the cans or jars are then set in 
a suitable flat bottomed boiler on thin slats (to prevent 
their breakage) and the boiler filled with water until it 
rises almost to the top of the jars. The boiler is placed 
over a fire and the water within is boiled for varying per- 
iods of time, depending upon the kind of food being thus 
sterilized. Tomatoes require only twenty minutes while 
corn requires from three to four hours. 

If glass jars are used, the tops and rubbers should be 
kept in the boiling water while the food is cooking and 
immediately after the jars are removed from the boiler, 
the tops should be tightly fitted on the jars. This insures 
thorough sterilization or the killing of all germs of f ermen* 
tation. 

"Preserving" is commonly done to "keep" peaches, 
pears, grapes, berries and like fruits. Usually a pound of 
sugar is added for each pound of fruit to be preserved and 
it is boiled for a time sufficient to make of the juice a 
rather thick syrup. No water is added as the cooking ex- 

103 



104 PHYSIOLOGY, HYGIENE AND SANITATION 

tracts enough, from the fruit to make the syrup. Such 
foods do not easily "spoil." 

Eggs may be stored for winter use by immersing them in 
a solution of "water glass," which can be obtained from 
drug stores, with instructions for its use. It is harmless 
and fresh eggs stored in the later summer months may be 
kept perfectly for use during the winter months when 
eggs usually cost a great, deal more money. 

Refrigeration has changed the market price of eggs, 
fruits, potatoes, meats, poultry, cheese and many other 
food products, and it saves from useless waste great quan- 
tities of foods every year. 

Such foods are preserved for later use by placing them 
in rooms artificially cooled by refrigeration. Nearly all ice 
plants in good-sized towns and cities have special rooms 
where, for a reasonable charge, food stuffs may be stored for 
later use. 

Large packing houses keep a large supply of meats, 
poultry, cheese and like products for many months. Fresh 
meats and similar foods are shipped by cars and steamers 
which are so constructed that a low temperature is main- 
tained to prevent the growth of the germs of fermentation 
or putrefaction. 

Pickling is another method of keeping meats and certain 
vegetables like cucumbers, cabbage and corn. Common salt 
is usually used for this purpose. Corn may be preserved 
for winter use by cutting it off the cob and packing it in 
an earthen jar. A layer of corn two inches deep is placed 
in a jar, this is covered with salt, another layer of corn 
and salt until the jar is filled. A clean plate is placed upon 
the mixture inside the jar and a weight used to keep all the 
corn under the brine which forms. A cloth is placed over 
the jar, which is kept in a cool place until ready for use. 



PRESERVATION OF FOODS 



105 



A quantity of corn for a meal is removed, rinsed in cold 
water and cooked as if it were fresh, from the cob, changing 
the water while cooking until free from salt. Vinegar is 
often used for keeping cucumbers and beets. 

Dehydratjion is a method used to preserve fruits, beans, 
corn and other vegetables. " Dried fruit" or vegetables 
is another name applied to food kept in this way. By ex- 
posure to the hot sun for a number of days, or by a slow 
heat in an oven, the water is evaporated from such foods 
until there is too little moisture for germs of fermentation 
to grow. These foods are then kept in a warm, dry place 
and used as needed. 

Dangers of Foods. 
Many foods when 
improperly manufac- 
tured, handled, kept, 
stored or sold may 
become dangerous to 
health. For this rea- 
son, atnd to protect 
the purchaser from 
substitutions and mis- 
branding, the U. S. 

Government has passed strict laws to prevent fraudulent 
claims for food products and their adulteration. "Look 
at the label" is a good rule to follow if you are desirous 
of securing your money's worth. 

The food markets should be kept clean, screened, and 
food for sale should not be exposed to the dust of the 
street or flies. The clerks should avoid handling food 
stuifs with unclean hands. Meat markets should be sup- 
plied with good refrigerators and they should be kept 
clean and free from putrefying meat. 




Fig'. 35.— A model food market. Observe 
the dust-proof cases and glass refrig- 
erators for meats. 



106 PHYSIOLOGY, HYGIENE AND SANITATION 

Oysters and fish should be kept on ice in dust and fly- 
proof containers; butter and cheese, in a fly-tight holder, 
supplied with ice; milk in a tight, well-chilled refrige- 
rator; lettuce, tomatoes, fruits and other foods eaten raw 
should be well protected from flies and dust and should 
not be handled with bare hands, because, many times 
such food thereby becomes infected with germs of typhoid 
fever or dysentery and is dangerous to health. For this 
reason, all foods eaten raw including apples, peaches, 
pears and grapes should be thoroughly washed in clean 
water before they are eaten. 

Summary 

Foods, such as certain vegetables, fruits, eggs and 
meats may be preserved for later use. Many of these 
foods during some seasons of the year are plentiful and 
cheap and are wasted, otherwise. 

"Canning" of vegetables and fruits may be done by 
thorough sterilization of the container and contents, by 
boiling for varying periods of time. 

Preserving of fruits is more expensive because much 
sugar is used, but less food is wasted through "spoil- 
ing." 

Eggs gathered during the later summer months may be 
kept for winter use by storing them in a solution of "water- 
glass," 

Meats, fruits and vegetables may be kept fresh for a long 
time by refrigeration. Pickling and dehydration are em- 
ployed to preserve certain fruits and vegetables. 

Foods may be dangerous to health if they are im- 
properly manufactured, stored, labeled or handled. For 
this reason, the United States Government and many 



PRESERVATION OF FOODS 107 

states have passed laws to protect people from careless 
or fraudulent dealers. 

Food markets should be kept sanitary and employees 
should avoid handling many food stuffs with soiled hands. 
Meat markets should be equipped with clean refrigerators. 

Oysters and fish, butter and cheese, lettuce, tomatoes 
and fruits require careful handling and protection from 
dust, flies and rodents. Fruits eaten with the peeling on 
should be thoroughly washed before they are eaten. 

Questions 

1. What is meant by preservation of foods? Why is 
it done? Name ten fruits and vegetables that may be 
"kept." 

2. What is canned food? What is necessary to "keep" 
canned fruit or vegetables from spoiling? Why? What 
is the commonest method of sterilizing foods? If rubbers 
and tops of glass jars are not thoroughly boiled what may 
happen? Why? 

3. What is the ordinary method of "preserving" fruits? 
What is the advantage and disadvantage of keeping fruits 
by this method? How may eggs be kept fresh for winter 
use ? 

4. What is meant by "refrigeration" as applied to 
foods ? Name six foods that may be kept for long periods 
by this means. How can fresh fruits such as strawberries 
be shipped long distances without "souring?" Why is 
this true? 

5. What is putrefaction of foods ? 

6. Name three meats and vegetables that may be pre- 
served by "pickling." What is a common chemical used 
for this purpose? 



108 PHYSIOLOGY, HYGIENE AND SANITATION 

7. How would you keep fresh corn for use during the 
winter months? How should it be cooked? 

8. What is meant by dehydration? What are " dried 
apples ?" Evaporated peaches, apricots and "raisins?" 
How may dehydration of fruits and vegetables be done? 
Why will such foods "mould' ' or "spoil" if kept in a 
warm, moist place? 

9. How may foods become dangerous? Why does a 
label on a package of food usually tell the truth ? 

10. How would you judge a food market to be properly 
conducted? Why are refrigerators necessary for meat 
markets? How should fish and oysters be kept or ex- 
posed for sale? 

11. Name five fruits and vegetables that should be pro- 
tected from flies, dust and rodents. Why? What is the 
danger of handling them with soiled hands? 



CHAPTER XV 



MILK 



This food, when pure, is probably the best food in the 
world. The human body is fed and grown for many 
months by the use of this food alone. Usually it is cheap 
enough in the open market to make it one of the most 
economical foods for use in the home. On the farm and 
in small towns it is easily procured and constitutes one 
of the chief articles of diet at a low cost. 

Milk improperly procured, handled or sold can easily 




Fig-. 36.— Showing- the reason milk is frequently unclean 
and dangerous. 

become infected with the germs of typhoid fever, 
dysentery, tuberculosis, scarlet fever, diphtheria and 
other infectious diseases. 

Care of Milk. On the farm and wherever cows are kept 
for supplying milk, a few simple rules should be followed 
to insure a clean supply of milk for the table. The cows 
should be kept in a clean barn and away from the mire 
and filth found in the barn-yards of many careless people. 
She should have clean bedding and her skin and hair 

109 



110 PHYSIOLOGY, HYGIENE AND SANITATION 



kept free from filth. Her udder and teats should be thor- 
oughly washed and dried before each milking. The hands 
of the milker should be thoroughly clean. The bucket 
should be cleaned, "scalded," and sunned between milk- 
ings. It should have only a small opening at the top to 
protect it from the entrance of dirt and flies or covered 
with a thoroughly clean, fresh cloth at each milking. 

The milk should be at once strained and placed in 
clean containers and set in an ice box or cool place. 

In a dairy 
these rules of 
clean 1 i n e s s 
should be fol- 
lowed in pro- 
curing the 
milk and it 
then should 
be placed at 
once in ster- 
ilized bottles 
and upon ice. 
The milk 
wagon should 
have provision made in hot weather for carrying milk 
packed in ice, and its sale from the street by pouring 
from an open container should be prohibited. 

Cows should be given the "tuberculin test" to deter- 
mine whether they are infected with tuberculosis and 
if so found, their milk should not be used or sold and 
should be killed for meat only when the health officer 
has passed upon its fitness for food. 

Dairymen should be required to obtain from health 
authorities a "permit" to operate a dairy, which pro- 





"" 


j^nj 


; ; | 


i 


1 • 












l«f €£ 



Fig - . 37.— A thorough-bred mlik cow, 
tuberculin-tested. 



clean and 



MILK 



111 




Fig-. 38.— A milk pail that ex- 
cludes much dirt while 
milking". 



teets the conscientious dealer 
from competition with un- 
scrupulous ones, and if the 
necessary regulations of the 
health board are not com- 
plied with, they should be 
fined and their license re- 
voked. 

" Market Milk" is a term 
used to apply to the mixed 
milk of a dairy herd; it is 
usually cheaper in price than 
"certified milk" which is produced under conditions ap- 
proaching the ideal and is fairly free from bacteria and 
contamination. Certified milk when it is on the market 
should always be bought, even at a higher price, for the 
feeding of babies and young children. 

Skimmed Milk is 
milk from which the 
cream has been re- 
moved by ' ' skim- 
ming" after stand- 
ing or by the use of 
a cream "separator" 
which operates 
quickly by centri- 
fugal force. It con- 
tains all the value of 
whole milk except 
the fat (cream). 

Butter is a by- 
product of milk 

marlp hv Ci ph^^rr\^r\P ,,, F iS"« 39.— A model milking stable for fur- 
indue vy oiiuinmg nishing clean milk, 




112 PHYSIOLOGY, HYGIENE AND SANITATION 

the cream of milk which has " soured" or undergone 
fermentation. 

Cottage Cheese is the "curd" of milk which has 
"clabbered" or undergone a form of fermentation. 

Buttermilk is a fermented milk remaining after the 
butter has been removed from it. 

Cheeses are of many 
kinds, depending for 
their appearance and 
flavor upon the process 
of manufacture and the 
curing of the curd ob- 
tained from the milk of 
the cow, sheep, goat or 
mare. 

"Watered milk" is a 
term applied to milk 
which has been adult- 
erated with water by dishonest dealers who charge the 
same price for it as should be charged for a standard 
or market milk. 

Summary 




Fig. 40. — This cow looks like a grood 
one. The germs of tuberculosis 
were found in her milk and she was 
killed. 



Milk is an economical food and easily procured. 
Under certain conditions, it can become a very dangerous 
food, for in it the germs of typhoid fever, dysentery and 
tuberculosis can easily grow. 

Cows should be kept clean by having fresh bedding 
every day, and their hair freed from filth. The cow- 
shed and surroundings should be kept clean. Milking 
should be done in a maimer to prevent dirt, flies and 



MILK 113 

impurities from getting into the milk. The containers 
must be thoroughly washed and sunned or sterilized. 
The milk should be at once strained and cooled and if 
it is sold on the market, bottled. 

Dairy cows should be tested for tuberculosis, and if 
infected, their milk must not be used for food or their 
meat should not be eaten, unless approved by the health 
officer. 

Dairies should not be permitted to operate unless a 
permit is secured from health officials, and if unclean 
milk is furnished, the license should be revoked or the 
owner of the dairy punished by law. 

Market milk is a term applied to milk which is usually 
sold from dairy wagons. 

Butter and- cheese are by-products of milk which have 
undergone certain kinds of fermentation. When the 
cream is removed from fresh milk, skimmed milk re- 
mains. Buttermilk is the sour milk remaining after but- 
ter has been removed from it by churning. 

Questions 

1. Why is pure milk a good food? What fact proves 
it contains all the classes of food needed to sustain life 
and build new cells? 

2. How can milk become dangerous? Name four dis- 
ease germs which grow easily in milk? 

3. Tell how pure milk may be placed upon the table 
ready for drinking, giving eight important steps in the 
production of such milk? Why is each step necessary 
to insure pure milk? 

4. What is the purpose of the tuberculin test? If a 
cow is so infected, what must be done with such a cow? 
Why? 



114 PHYSIOLOGY, HYGIENE AND SANITATION 

5. What is a dairy? Why should a permit from a health 
officer be secured to operate a dairy? Name five bad 
conditions found at a dairy which would be sufficient 
cause for a permit to be revoked by health authorities? 

6. What is market milk? "Certified milk?" 

7. Why should "certified milk" be procured, when 
possible, for young children? 

8. What is "skimmed milk?" What is its food value 
as compared to whole milk? 

9. How is butter made? What is responsible for the 
"souring" of milk? What is buttermilk? 

10. What is cottage cheese? Upon what does the flavor 
and appearance of cheese depend? 



CHAPTER XVI 

WATER 

Water for drinking purposes is obtained from wells, 
cisterns, springs, lakes, artificial reservoirs and running 
streams. 

Wells are shallow or deep, depending upon the depth it 
is necessary to dig or drill them to reach the under- 
ground streams which supply them. 

Artesian wells are drilled to the depth of several hun- 
dred feet, usually, and furnish a large supply of water 
which is forced by pressure out of the well at the surface 
of the ground. Such water is nearly always pure. Potable 
water, or water for drinking purposes, implies that it 
shall be free from disagreeable odors, clear in color, free 
from sediment, and contain no bacteria, showing pollu- 
tion by surface drainage. 

Shallow wells either "dug" or drilled may furnish a 
supply of clear water in an isolated place far enough re- 
moved from alleys, stables, surface closets and other 
sources of pollution. Well water, spring water or cistern 
water, which becomes muddy after a rain, should be un- 
der suspicion as dangerous, for it is evident that surface 
water, which may be filled with filth and disease-producing 
germs, has found its way either through the top, along 
the walls or into a stream which is a source of supply. 
In certain limestone districts, such polluted water from 
the surface, following a rain, may be carried long dis- 
tances through fissures or cracks in the stone. Shallow 
wells and springs should never be used as sources for 
drinking water in densely populated districts. 

A properly constructed cistern probably furnishes the 

115 



116 PHYSIOLOGY, HYGIENE AND SANITATION 



safest supply of water in such districts where it is not 
supplied by a system of pipes from a reservoir, deep 
wells, lake or river, under such regulations as are neces- 
sary to insure its purity. A cistern should be large 
enough to furnish plenty of water through the summer 
months without having to use the summer rains. Its 

bottom and walls 
should be lined with 
brick and coated 
over with cement so 
that it is water-tight. 
A filter is an appli- 
ance to remove, me- 
chanically, certain 
foreign substan c e s 
from water. A sim- 
ple one for use, hold- 
ing about two barrels, 
in connection with a 
cistern, may be con- 
structed of brick, lin- 
ed inside with cement 
and connected at its 
bottom to the "feed 
pipe" leading to the 
cistern. In it are 
placed layers of charcoal, sand and coarser gravel. It is 
provided with a tightly fitting top, through which the 
pipe runs from the roof or other surface where "rain 
water" is collected by the use of gutters and conducted 
Through the filter into the cistern. The contents of such 
a filter should be changed at least twice during the time 
water is being collected through the winter months. Be- 




Fig. 41.— A dangerous cistern. There is 
no filter. It has a leaky top and the 
surroundings look bad. 



WATER 



117 



fore filling it, the cistern, the filter and gutter should be 
thoroughly cleaned and a number of hard rains allowed 
to fall so that the roof may be thoroughly washed free 
from dust and other impurities carried by rodents, birds 
or the wind. The tops of wells and cisterns should be 
water-tight and so constructed that surface water or 
spilled water cannot drip or filter through into the water 
supply. The open-top well or cistern is dangerous and 
water should not be drawn with a bucket and rope which 
often is permitted to become fouled on the platform where 




Fig-. 42.— Showing- why shallow well water is often 
polluted. 



children, chickens, dogs or other animals may carry pollu- 
tion on their feet. It is best to have a concrete top which 
extends down the walls of the well or cistern for three or 
four feet and far enough from its top and around it to 
provide for drainage of rain-water and that spilled or 
wasted at the pump. 

Polluted Water. Water is polluted when it receives 
surface drainage. It is customary to think of spring water 
or well water as being pure because it may be clear and 
cold. It is only necessary to remember that wells and 
springs are simply streams of water resulting from the 



118 PHYSIOLOGY, HYGIENE AND SANITATION 

rains, that have found their way from the surface of the 
ground. If the surface from which such water comes 
is a foul alley, stable yard or surface closet, the water is 
polluted and unfit for drinking purposes. Such water 
may not contain, at all times, the germs of typhoid fever 
or dysentery, but if some one is ill nearby and proper 
methods for killing the disease seed which come from such 
a person are not used, such water from that neighborhood 
may contain germs of these diseases and upon being drunk 
by healthy people, may cause them to have like diseases. 
Examination of Water. If drinking water becomes 
muddy after rains or has a disagreeable odor, or contains 





-• 




■ 


^3 v \ : ~H 


. w$. 


•"' ^■••^;:^^:?^:Si%gi;; 


8 











Fig-. 43.— A large sand and gravel filter for a city's 
water supply. 

tiny living animals or is being obtained from a well, spring 
or cistern, near a case of illness from typhoid fever or dys- 
entery, it should be examined to determine its fitness for 
drinking purposes. In any event, it can be made safe for 
use by boiling 1 for ten minutes. A chemical examination 
of water may reveal the presence of organic matter, either 
in its pure state or in its process of reduction into inorganic 
salts. Such an examination may be furnished, free of cost, 
by the state health authorities to any citizen of the state. 
A bacteriological examination is made to show the presence 
or absence of any living germs in water. The colon bacillus, 
or the germ that is found in the intestines or bowels of all 



WATER 



119 



animals, is the index for determining the safety of drink- 
ing waters. If this germ is found in fairly large num- 
bers, the water is condemned for drinking purposes, for it 
shows that such water is receiving drainage from stables 
or like foul places and may, if typhoid fever or dysentery 
appears in the neighborhood, transmit these diseases to 
users of the water. Such an examination is usually made, 
free of cost, to any teacher, householder or citizen of the 
state, upon request to the state health authorities. 

Purification of Water. 

Water found in rivers 
and small streams is 
usually polluted b y 
drainage from the more 
or less populated coun- 
try forming their water- 
sheds. The Ohio river, 
for example, is but a 
vast sewer, which con- 
stantly receives all the 
wastes from hundreds 
of cities and towns, 
water for drinking pur 
poses is made dangerous for this reason unless it is prop- 
erly purified. It is not practical to boil all the water 
needed by a large city or town. It is, therefore, purified by 
sedimentation Alteration and treatment with certain chem- 
icals, as chlorine. By sedimentation is meant the process 
of separating the suspended, solid matter in water from it, 
thus restoring its clarity. A chemical, usually alum, is 
added in solution to the water to be treated, and in a 



\ 






\/ 






I\ 












1 \ 


\ 






\ 








\/ 






-_;-■; \. 



Its Fig-. 44.— Showing- the way to make a 
drinking cup by folding a clean 
sheet of paper. 



120 PHYSIOLOGY, HYGIENE AND SANITATION 



specially constructed tank or reservoir, of sufficient size 
to supply a community with, enough water, the water is 
made to pass slowly through the tank by means of incom- 
plete partitions (baffle walls) and when it reaches the out- 
let pipe at the upper and most distant end, the solid matter 
causing its turbidity has settled to the bottom and only 
clear water it withdrawn. It is sometimes necessary to 
supplement this action on water by Alteration. Fjilteration 
is a plan of treating water through filter beds of sand, coke, 
gravel or some similar substance to remove foreign matter, 

including bacteria. 

Chemical treatment 
of water is often nec- 
essary to purify it 
for cities, towns or 
homes. In large 
plants liquid chlorine 
is added to water in 
the proportion of 
about three parts to 
the million of water, 
which kills the ordi- 
nary germs in water liable to produce disease. A like 
amount of fresh chloride of lime or ' ' bleaching powder, ' ' 
added to water, is a method of purifying it in schools, 
homes or small towns. One grain of potent chloride of 
lime thoroughly mixed with five gallons of water is suf- 
ficient to purify it within twenty-four hours. Chloride of 
lime, exposed to air, soon loses its chlorine and is of no 
more value than chalk for this purpose. 

The Common Drinking Cup is a dangerous weapon. 
Its use should be prohibited in schools, hotels, public of- 
fices and all public places. It may easily carry infections 




Fig-. 45.- 



-A common drinking* cup is too 
''common" to use. 



WATER 121 

of tuberculosis, diphtheria, influenza, scarlet fever or one of 
the vile social diseases, from a person so infected, to a 
healthy person. Every person should carry a cup when 
traveling or at school and forbid its use by others. Indi- 
vidual drinking cups may be cheaply made of waxed 
paper by folding it successively. 

Drinking Fountains should be installed in schools, depots 
'and other public places where a number of people must 
quench their thirst. They are so arranged that a stream 
of water is made to bubble up from a spout over which, 
but not touching it, the mouth is held and by slight suc- 
tion the thirst may be satisfied. There are a number of 
these on the market but one may be easily constructed, 
.care being used to insure a clean and fresh supply of pure 
water at all times. 

Summary 

Water for domestic use is obtained from wells, cisterns, 
springs, lakes, rivers and artificial reservoirs. Artesian 
wells usually supply a potable water. 

Shallow wells and springs in thickly settled communi- 
ties are liable to furnish an unsafe water for drinking 
purposes. 

Cisterns, when built right and carefully managed, are 
safest to use for storing water, when this is necessary. 

A cistern should always be provided with a good filter, 
and it should be cleaned at least twice a year. Care must 
be used in collecting winter rains for a supply of water for 
cisterns. An open-top well or cistern is unsafe, and each 
should be provided with a well-fitted pump and concrete 
top and sides so that surface or spilled water is not per- 
mitted to enter. Surface water from foul places is danger- 



122 PHYSIOLOGY, HYGIENE AND SANITATION 

ous to drink and may contain germs of typhoid fever or 
like diseases, if any one having such illness lives near 
such a supply of water. Well water, or water from springs, 
or badly built cisterns, which becomes muddy after rains, 
may be unsafe to drink and it should be boiled before using 
it for drinking purposes. It then should be examined, 
chemically and microscopically, in a laboratory where or- 
ganic matter or bacteria may be found present or absent. 
When colon bacilli are found in drinking waters, it proves 
that the water from a foul surface is reaching the supply 
and such water is dangerous to drink. 

Water from rivers and small streams, in populated dis- 
tricts, is usually polluted. When great quantities of 
water are to be supplied, as in cities, water from rivers is 
usually used. It is first purified by chemical and me- 
chanical means. Sedimentation and Alteration are the 
methods usually employed. Three parts of chlorine to a 
million parts of water are enough to kill typhoid germs 
in drinking water within twenty-four hours. 

Fresh chloride of lime contains chlorine and may be 
used to sterilize drinking water for schools, homes and small 
water plants. The use of a common drinking cup is pro- 
hibited by law in many states. 

A drinking fountain should be used in public places, 
so that a fresh supply of pure water may be supplied to 
each person without danger of becoming infected with 
tuberculosis, diphtheria and similar diseases. 

Questions 

1. Name six sources of drinking water. 

2. What supplies wells and springs with water? What 
are artesian wells ? 



WATER 123 

3. "What is a potable water? Under what circumstances 
may wells or spring water be potable? How may water 
in wells or springs become infected in limestone countries? 

4. When should cisterns be constructed? Tell how a 
cistern should be built? What is a filter? How is it 
used ? Is it necessary to change the contents of a filter ? 
Why? Why should the roof of a building, from which 
water for the cistern is collected, be washed? How is it 
washed ? 

5. How would you keep surface or spilled water from 
finding its way into a well or cistern? Was the "Old 
Oaken Bucket " a safe way to supply water? Why? 

6. How is water often polluted? What is polluted 
water? Why is such water dangerous to drink? 

7. What diseases may be spread by the use of polluted 
water? Why are such disease seed sometimes found in 
water ? 

8. Give four reasons why drinking water should be 
examined. What is the quickest and easiest way to make 
a dangerous water safe to use? 

9. How is organic matter found in water? What is a 
bacteriological examination of water? What does it 
mean if the laboratory report shows the presence of colon 
bacilli in water? 

10. Why is river water usually polluted? How is it 
purified for use in cities? 

11. What is sedimentation of water? How is it done? 

12. What is meant by Alteration of water? How is 
it usually done? 

13. What chemical is used by cities to kill bacteria in 
water? What strength solution is used? 

14. What is bleaching powder? How would you use 



124 PHYSIOLOGY, HYGIENE AND SANITATION 

it to purify water for use in schools? How would you 
keep it potent? 

15. Why is the common drinking cup dangerous ? What 
diseases may be spread by its use? Make a drinking cup 
by folding a piece of clean paper. 

16. What is a drinking fountain? Where should one 
be used? How is it arranged? How is it used? 

17. If a drinking fountain is provided and its source 
of supply is a tank or barrel, which is left open or is 
not cleaned or filled with pure water, of what value is it? 
Why? 



CHAPTER XVII 

THE TEETH 



Food before it can be absorbed and assimilated in the 
body cells must be reduced to a liquid. Solid foods, as 
meats and vegetables, must be reduced or ground to small 
pieces by chewing. The process of mastication, insaliva- 
tion, already described, reduces the food to a "pulp," or 
half -liquid mass. 




Fig-. 46.— The temporary or "milk teeth." 

The teeth, therefore, are one of the most important aids 
to perfect digestion. 

Why do not young babies have teeth? 

During a lifetime nature supplies the body with two 
sets of teeth. The first set of teeth is called temporary 
teeth and are twenty in number, ten in each jaw. They 
become loose and yield their places, beginning at about 
the age of six years, to the permanent teeth, thirty-two 
in number, sixteen in each jaw. The permanent teeth at 

125 



126 PHYSIOLOGY, HYGIENE AND SANITATION 

the age of twelve years have usually appeared, with the 
exception of four back teeth, which are called "wisdom" 
teeth, and these appear near the age of twenty-one. The 
first molars of the permanent set appear near the age of 
six years. 

Structure of Teeth. Teeth are bone-like in their struc- 
ture. A tooth is made up of a crown, the neck and the 
root. 

The crown is the part showing above a healthy gum, 
and is covered with enamel, a glistening, hard material 




Fig\ 47.— The permanent teeth. 

which is made to stand a great deal of grinding, without 
wearing away. The neck of the tooth is the part covered 
by the gums and often shows, when a disease (Biggs' or 
Pyorrhea) has caused the teeth to become loosened. The 
root may be a single one, as in the front teeth, or double, 
as in the lower "jaw" teeth, or three-pronged as in the 
upper jaw teeth. 

If a tooth is sawed across, three parts are seen. In 
the center is a soft mass which contains nerves and blood 
vessels. Surrounding this pulp, is a hard, bony mass, in 



THE TEETH 



127 



which are blood vessels and nerves for supplying the 
tooth with nourishment. The outside layer is the 
enamel, which is the hardest substance in the body, and 
receives no blood supply. For this reason, if it becomes 
broken off or is permitted 
to decay, it is not rebuilt 
and the tooth is in danger 
of being destroyed. The 
root of a tooth is planted 
firmly in the jaw bone 
and surrounded by a sup- 
porting, bony structure 
called cement. It is 
through the root that the 
nerves and blood vessels 
reach the pulp chamber. 

The Shape of Teeth. 
It will be seen that the 
four front teeth (the in- 
cisors) are broad and 
sharp like a chisel. These 
are used for cutting food 
into smaller pieces; back 
of these are teeth pointed 
like a pencil (the canines) 
and back of these are 
teeth with broader, flater, 
grinding surfaces ( the 
bicuspids and molars.) 




Figr. 48. — Showing- the struc- 
ture of a tooth. A. Enamel 
B. Dentine. C. Pulp 
chamber with nerves and 
blood vessels. D. Cement. 



Decay and Injury of Teeth. Teeth may be injured by 
falls, blows and muscular efforts in biting upon some hard 
substance as nuts or metal. Teeth loosened by a fall or 
blow may become firmly fixed again, if a competent den- 



128 PHYSIOLOGY, HYGIENE AND SANITATION 

tist is consulted, who can anchor them tightly until na- 
ture repairs the cement about their roots. If the enamel 
is cracked, it should at once be repaired by a dentist, who 
will enlarge the opening, destroy the infection and fill 
it with a metal like gold or an alloy of metal, or cement. 
This prevents decay. 

By decay of teeth is meant a destructive action upon 
the enamel and body of a tooth by certain bacteria, which 
are always found in the mouth. These bacteria find in 




Fig-. 49. — Teeth lost from neglect. The only remedy is 
a "bridge" or "plate." 

the dark, warm, moist mouth, when food is not washed 
after each meal from the teeth, an ideal place for growth. 
Their growth produces an acid about the teeth which 
chemically destroys the lime salts in the enamel and body 
of the teeth. When once a hole is made in the enamel, 
destruction of the softer body of the tooth is rapid. The 
nerves are then exposed and "toothache" results. This 
pain is nature 's kindly warning that a tooth is being de- 
stroyed, and should be regarded as her appeal for its re- 
pair. 

Care of the Teeth. No one would think of preparing 
food with a meat grinder, if it were not thoroughly washed 
each time after being used. It would become foul and 
have a disagreeable odor and the germs of putrefaction, 
when eaten with food prepared with an unclean grinder, 



THE TEETH 



131 



Repair of Teeth. It is far better to prevent the decay 
of teeth than to repair them. One should go to a good 
dentist, at least, twice a year and have the teeth examined 
and repaired, if needed. 

If "tartar" has collected around the gum, it should be 
removed. In the first appearance of "toothache" the 
tooth should be repaired or "filled." 

Kiggs' Disease or Pyorrhea, causes the gums to re- 
cede from the teeth and they become loosened. This con- 




Fig 



-Showing- how the permanent teeth displace 
the temporary ones. 



dition calls for immediate treatment by a dentist until 
the trouble is relieved. 

When teeth are so badly neglected that some of them 
have been extracted, or "pulled," a dentist may be able 
to fill the gap with false teeth by means of a "bridge." 
This restores the function of the teeth and if the front 
teeth have been lost so that bridges may not be employed, 



132 PHYSIOLOGY, HYGIENE AND SANITATION 

a " plate " containing one or several teeth may be made 
by the dentist. If, for any reason, all of the teeth in the 
upper or lower jaw, are lost, a set of " false teeth" can 
be used. False teeth should be secured only as a last re- 
sort for they are not sightly, interfere with speech, become 
foul quickly and require frequent cleansing. 




Figr. 53.— A properly equipped dentist's office. 

Summary 



The teeth are important organs of digestion being 
used to help reduce coarse foods to a liquid ready for ab- 
sorption. 

The temporary teeth, twenty in number, begin to make 
their appearance during the first year of life and are 
usually displaced at the age of twelve by the permanent 
teeth, thirty-two in number. 

The crown, root, and body compose a tooth which is 
covered on its exposed surface with enamel. The gums 
cover the body of a tooth and its root is firmly cemented 



THE TEETH 133 

in the jaw bone. Blood vessels and nerves enter the pulp 
chamber of a tooth through the root, and are distributed 
throughout the tooth to supply it with nourishment. 

Teeth are shaped for cutting, tearing and grinding food 
and are named incisors, canines, bicuspids, and molars. 
They may be injured by mechanical or violent means or 
may decay by the action of bacteria which produce an 
acid which dissolves their mineral salts. Unless the teeth 
are kept clean, decay results and they are finally de- 
stroyed, causing much pain and even ill-health. 

A competent dentist should be consulted twice a year 
to inspect the teeth and repair them, if needed. Bridges, 
plates, and false teeth can be made to do the work of 
missing teeth. 

Many times rheumatism or heart disease follow infec- 
tions or abscesses at the root of badly decayed teeth. 

Questions 

1. What is the principal function of the teeth? Why 
are teeth necessary for digestion of food? 

2. What is insalivation ? Mastication? 

3. What is the best evidence to show that very young 
babies should not be fed solid foods? 

4. What are the temporary teeth ? How many ? When 
do they- begin first to appear? What take their place? 
Can you explain why there are twelve more teeth in the 
last set? What are "wisdom" teeth? 

5. When does the first jaw tooth of the permanent teeth 
appear? Should a decayed jaw tooth of a child of seven 
years be pulled without consulting a dentist? Why? 

6. What is the crown of a tooth ? The body ? The root ? 
What is enamel? What is meant by the gums? 



134 PHYSIOLOGY, HYGIENE AND SANITATION 

7. How would you suspect one might have Riggs' Dis- 
ease? What other name has it? 

8. Why do you think the jaw teeth have spreading 
roots? 

9. What is the "pulp" of a tooth? What is its func- 
tion or use? Does blood circulate through the body of a 
tooth? Why? Does it flow through the enamel of a 
tooth? Why? 

10. If enamel is cracked or broken, does nature rebuild 
it? Why? 

11. Can you think of any reasons why the shape of the 
teeth proves that man eats both animals and vegetables 
for food? Why are dogs', cats', lions', and tigers' teeth 
of the pointed, sharp kind? 

12. How may teeth be injured? If a tooth is loosened 
by violence, must it be pulled out? Why? What should 
be done with it? 

13. Why do teeth decay? Explain why bacteria cause 
decay of teeth. What is toothache? Explain why it 
may be considered a "blessing in disguise." 

14. Show why unwashed teeth are filthy? How they 
may cause ill-health. How can decayed or unclean teeth 
cause a "bad breath?" 

15. How may teeth be cleaned? How often and when 
should teeth be "brushed?" 

16. How would you prevent decay of the teeth? Is it 
wise to wait for a toothache before consulting a dentist? 
Why? 

17. Can pyorrhea be cured ? What would you do if you 
suspected you had it? How may one suspect that pyor- 
rhea is present ? 



THE TEETH 135 

18. What is a "bridge"? What is its need and pur- 
pose? When may a "plate" be used? 

19. What is meant by a "set of false teeth"? Give four 
reasons why they should be secured only as a last re- 
sort? 

20. Name two diseases sometimes caused by badly de- 
cayed and abscessed teeth? Explain how this occurs. 



CHAPTER XVIII 



THE CIRCULATORY SYSTEM 

In the preceding chapters it was shown that the body 
must have food to furnish* it with energy, heat, and to 
repair its parts. This food must be digested and ab- 
sorbed into the blood ready for assimilation. Not only 

must the bodv cells have 






food but they must be sup- 
plied with oxygen from the 
air. The body must also, rid 
itself of poisonous wastes 
and dead cells which result 
from the expenditure of en- 
ergy and the production of 
heat. These operations are 
carried on through the cir- 
culation of the blood and 
lymph. 

If a cut is made through 
any part of the skin, at once 
there appears a flow of a red fluid, the blood. It flows 
through every part of the body except in the hair, nails, 
enamel of the teeth, and outer layers of the skin. 

If any part of the body is deprived of blood for a few 
hours, it dies. 

For hundreds of years it was not known that blood 
circulates through the body and when Harvey of Eng- 
land in 1628 proclaimed his discovery, he was ridiculed 
and persecuted before his observations were proved. Now 
every school child knows something of the circulation 
of the blood and its functions. 



Fig-. 54. — Red blood corpuscles. 
They often are collected in 
rolls like coins. 



136 



THE CIRCULATORY SYSTEM 



137 



So necessary is it to maintain life, that if the circula- 
tion should stop for a few minutes, death of the whole 
body and its millions of cells would result. 

The functions of circulation, then, are to carry oxygen 
to the body cells ; to furnish them with food and water ; 
to carry away wastes, to preserve an even degree of heat 
in the body, and to aid in the defense of the body against 
disease. 

The Blood. The blood is a red, sticky opaque fluid 
with a peculiar odor and a salty taste. It is a bit heavier 
than water. It is neither an 
acid nor alkali (or salt). 
It comprises about seven and 
one-half per cent of the body 
weight or about six quarts 
for an average man. 

If fresh blood is caught 
in a vessel and allowed to 
stand, it will be noticed that 
it becomes thicker, or more 
viscous, and later sets into a 
firm jelly. If not molested, 
the mass contracts and a 
clear straw colored fluid, the serum, appears 
solid mass is a "clot." 

The blood is composed of plasma and corpuscles. The 
plasma is the fluid part of blood and it may be called 
the blood minus the corpuscles. 

Corpuscles are cells suspended in the plasma of the 
blood. They are of two kinds, the red and the white. 
The red are smaller than white corpuscles and outnum- 
ber them five hundred to one. The red corpuscles, carry 
oxygen to the tissues and collect carbon dioxide from 




Fig. 55.— The large one, a white 
corpuscle in about 500 red 
ones. 



The more 



138 PHYSIOLOGY, HYGIENE AND SANITATION 

them. The white blood cells carry food to the body cells, 
collect wastes and destroy germs that threaten the life of 




Fig-. 56.— The heart, showing- large blood vessels, 
positions of its right chambers. 



and 



cells, and have the power of self-movement. They are 
sometimes called the "wandering cells." 

The blood is carried to every part of the body 
through the action of the organs of circulation ; these 



THE CIRCULATORY SYSTEM 



139 



are the heart, arteries, capillaries and veins and lymph- 
atics. 

The Heart. The heart is a pear-shaped, hollow, muscu- 
lar organ about the size of one's fist. It is in the chest 
a little to the left of the middle of the breast bone 
(sternum) and its "beat" can be plainly felt in this 
region. It is enclosed in a sac called the pericardium. 

The heart is a pump and a wonderful one it is. It has 
four cavities, two auricles and two ventricles. All the 
blood of the body is 
emptied into the ventricles 
where it is pumped 
through every part of the 
body. The right side of 
the heart receives the 
blood as it returns from 
its trip through the body 
and pumps it through the 
lungs where' it is purified. 
The left side of the heart 
receives the blood from 
the lungs and pumps it 
throughout the body. It 
is evident that the left side of the heart 
stronger. Why ? 

The walls of the left ventricles are much thicker than 
the walls of the right ventricle, and the wslII^ °f the 
auricles are thin for their only work is to force the blood 
into the ventricles below. 

The heart pumps the blood by the contraction of its 
muscular walls very much like water is forced out. of a 
hollow rubber ball by squeezing it with the hand. If one 
squeezes a soft rubber pipe filled with water, the water 




Fig - . 57.— Showing- the valves of the 
heart. The folds close tight at 
the proper time and the blood is 
forced onward in its course. 



must be the 



140 PHYSIOLOGY, HYGIENE AND SANITATION 



is forced out of each end. If one end of the tube is plug- 
ged, all the water will be forced out of the other end. 
So it is evident that some arrangement has been made 
to keep the blood moving onward on its course when the 
muscles contract. This is done by means of valves placed 
between the auricles and the ventricles. These valves 

are thin mem- 
branes so arrang- 
ed that no resist- 
ance is made to 
the flow of blood 
from the auricles 
into the ventricles, 
but when the 
heart pumps, 
these valves at 
once close tight 
and no blood is 
permitted to 
squirt backwards. 
Some diseases like 
' ' rheu matism" 
often cause these 
valves to leak and 
some blood is permitted to escape back into the auricles, 
and a curious sound is made by the blood passing be- 
tween them. This is called a "leaky heart." 

The Work of the Heart. The heart beats in an adult 
about seventy-two times every minute. In health its 
work is regular and time is given between each beat for 
the heart to rest. It is the hardest-worked organ in the 
bodv and its work everv day is as much as would be 




Pig-. 58.— Arteries of side of the face and 
head, showing- how arteries divide into 
smaller branches. 



THE CIRCULATORY SYSTEM 



141 



done, if a man carried two hundred pounds to the top 
of a mountain two thousand feet high. When the muscles 
of the body are active, as in exercise, the heart's action 
is more rapid and greater effort is made each beat to 



%' S3 W? 



f^eV*^ 







Fig-. 59.— Showing- the general plan of circulation from the left 
heart through the arteries, capillaries and veins of the body, re- 
turning to the right heart, thence through the arteries and capil- 
laries of the lungs and returning to the left heart. 



142 PHYSIOLOGY, HYGIENE AND SANITATION 



keep up the circulation of the blood. Athletes soon de- 
velop a strong heart muscle and if training is abruptly 
stopped, the heart may be impaired. For this reason one 
accustomed to much physical exercise should grow grad- 
ually accustomed to a sedentary life, if it becomes neces- 
sary, and regular exercise practiced daily. 

The heart is nourished by its arteries, veins and capil- 
laries. The heart arteries have their origin from the large 
single artery (aorta) which leaves the left ventricle. 

The Arteries. Imagine what a com- 
plex framework of pipes there would 
be in a city water-works if all of the 
pipes could be freed from the structures 
which conceal them. 

There would be a main pipe line run- 
ning from the reservoir to supply each 
house in the city. There would be large 
and small pipes branching from the 
main one, and still smaller ones which 
would supply each house ; from the 
pipes leading to each house, there 
would be smaller ones to supply each 
room, until finally there would be seen a great network 
of pipes, large and small, through which water for the 
city could be supplied to every part of it. 

The arteries of the body operate very much in this way. 
From the heart, which may be called the "reservoir," 
there are two large arteries (or pipes) one (the pulmo- 
nary) leading from the right ventricle to the lungs, and 
the other (the aorta) which is very much larger, leading 
to every organ, muscle, bone, and structure in the body. 
As the arteries pursue their way through the body, they 
give off branches, here and there, which become smaller 




Figr. 60. — A capil- 
lary cut across, 
showing- blood 
cells in the tiny 
tube (greatly 
magnified). Note 
the white blood 
cells escaping 
through the wall. 



THE CIRCULATORY SYSTEM 143 

and smaller as the distant parts are reached until, finally, 
they are so small that, with the naked eye, it cannot be 
seen they are "pipes" or tubes at all. These tiniest of 
arteries are called arterioles. 

Structure of Arteries. The arteries are so constructed 
that they expand and contract as each new volume of 
blood is pumped into them. This is done for two reasons ; 
to relieve the work of the heart and to make an even, con- 
tinuous flow through the capillaries. At the exit of the 
heart, both the aorta and pulmonary arteries have valves 
arranged so that when the arteries recoil after being 
stretched by the heart beat, no blood can be forced back 
into the heart. By this arrangement the blood is forced 
on its way to all parts of the body. When an artery is 
cut, the blood, bright red, escapes in a "spurt" at each 
beat of the heart. 

The Capillaries. When an artery has been divided and 
subdivided until its smallest branches (the arterioles) are 
reached, the blood enters the capillaries. The opening 
through them is often so small that tiny blood cells must 
make their way, one by one. If the tail of a living tadpole 
is spread upon a tiny glass and placed under a microscope, 
the blood cells may be seen winding their way through the 
capillaries. Their walls are very thin, having only a single 
layer of cells, held together by a "bit of connective tissue. 
It is in the capillaries that body cells receive their food 
and give up their wastes. 

Veins. As the capillaries begin to unite themselves into 
larger tubes, veins are formed. These tiny veins connect 
with one another, making larger veins until finally they 
all merge into two large veins, which return the blood 
into the right auricle of the heart. In the veins are placed 
at intervals of one to several inches, folds of membrane, 



144 PHYSIOLOGY, HYGIENE AND SANITATION 

so arranged that blood cannot flow backwards, but with 
the force of the heart, pushing the blood along, and by 













■ Jjk. 












yWm 










HKgpf-~7? 




^~~~Z ZZZ 




•*. _,„,->«■ 








£&*£/ 














^ : K 








Jm V SI 


N£ .!■< _ 


***jx*»m, 








WN 11 


' / ^-/y^ 






IfflC^ 


}*■%'% ■ 




'>'t^ 




^ J 




w% 


■W^l 




"t 








pi 

llSr f \ M 

If*. I' \ li 






• 






9 ||-:| : ,jf 



Fig-. 61.— Showing- lymphatic glands under the arm and 
the lymphatic vessels which carry lymph through 
them. 



the contraction of the body muscles, the blood is made to 
return to the heart. When a vein is cut the blood (dark 
red) flows in an even stream. 



THE CIRCULATORY SYSTEM 



145 



The blood cells have now 
given up some of their food 
to the body cells and have 
collected waste materials 
from them, and it must now 
be pumped through the lungs 
to be purified in their capil- 
laries and brought back 
through the veins to the left 
heart to be again pumped on 
its life-saving journey 
through the body. 

The Lymphatics. One 
wonders where body cells 
get their nourishment, and 
when the change of food into 
flesh is made. If the blood 
circulate continuously, does 
it stop long enough to give 
up its food, or does it do it 
"on the run?" This process 
is carried on in the lymph- 
atic vessels. 

Blood plasma, the liquid 
part of the blood which con- 
tains the white blood cells, 
does not always accompany 
the red blood cells. 

As the blood goes through 
the capillaries, the blood 
plasma, carrying its white 
cells with nourishment, es- 
capes through the walls of 




Fig - . 62.— Outline of the circu- 
lation of the blood. L. A. 
Left auricle. L. V. Left ven- 
tricle. R. A. Rig-ht auricle. 
R. V. Ri§rht ventricle. P. A. 
Pulmonary artery to lungs. 
P. V. Pulmonary vein from 
lungs. U. P. K. Capillaries 
of upper part of body. L. E. 
K. Capillaries of lower part 
of the body. A. Aorta. V. Re- 
turning veins. 



146 PHYSIOLOGY, HYGIENE AND SANITATION 

the capillaries into tiny spaces around them. This fluid 
is now called lymph, which is another name for blood 
plasma. These spaces are the peri vascular spaces, or the 
beginning of the lymphatics. It is here that the body cells 
are bathed in blood plasma and each cell may take what 
food it needs from the white cells and they, in turn, pick 
up its waste matter. 

From these very small lymphatics, the blood plasma 
flows through connecting channels, very much like the 
blood is collected into the veins from the capillaries, and 
finally empties into two large tubes. These tubes enter 
directly into the deep veins in the right and left shoulder 
and their lymph is returned with the blood to the right 
heart. Lacteals are lymphatic vessels which take up fatty 
portions of the digested food from the small intestines 
and carry it, with the lymph, to the circulation through 
the large lymphatic vessels in the neck. Lymphatic ves- 
sels have valves similar to those found in the veins so 
that the flow of lymph is maintained in only one direc- 
tion towards the large veins in the region of the shoulder. 

Lymph Glands. As the lymphatics pursue their way 
through the body they pass through many whitish bodies 
of varying sizes, the largest being about the size of a 
grape. Here the lymph is filtered or "strained" and 
bacteria that have found their way into the blood are 
made prisoners, as it were, and destroyed by the white 
blood cells. A "kernel" under the arm, or in the thigh 
is an enlarged lymphatic gland or node, which has "taken 
prisoners" some germs from some "sore" or infected 
place lower down the arm, body or leg. 



THE CIRCULATORY SYSTEM 147 

Summary 

The circulation of blood and lymph is necessary for 
the assimilation of food, the production of heat and 
energy and for the defense of the body against disease. 

The blood is composed of plasma and red and white 
corpuscles, and it is carried to every part of the body 
by the heart, arteries, veins, capillaries and the lymph- 
atics. 

The heart is enclosed in the pericardium and is divided 
into two auricles and two ventricles. 

The blood flows through the left auricle into the left 
ventricle into the aorta and through branching arteries. 
It enters the capillaries and is collected by connecting 
veins and returned to the right auricle ; from there, it 
flows into the right ventricle, into the pulmonary artery 
and through the capillaries of the lungs where it is re- 
turned, purified, through the veins, into the left auricle. 
The same beat of the heart performs at one time the 
work of both sides of the heart. 

Lymphatics collect blood plasma from the spaces 
around the capillaries into larger lymphatic vessels and 
empty the lymph into large veins near the neck. 

Questions 

1. Name five functions of the circulation. "What two 
fluids make up the circulation? 

2. When and by whom was the circulation of the blood 
discovered? 

3. How do you know that circulation is necessary to 
maintain life? 

4. What is blood? How much blood in an average 
man? 



148 PHYSIOLOGY, HYGIENE AND SANITATION 

5. What is a "blood clot?" Blood serum? 

6. Of what is blood composed? What is the function 
of red blood corpuscles ? Of the white corpuscles ? What 
is plasma? 

7. Describe the heart. Where is its location in the 
body? 

8. What are the auricles? The ventricles? 

9. Is there any flow of blood between the auricles? Is 
there any flow of blood from the left ventricle to the 
right ventricle? 

10. What is meant by "right heart?" The "left 
heart?" 

11. How does the heart compel the blood to circulate? 
Illustrate its action. 

12. What arrangement is made in the heart to keep 
the blood flowing onward through the blood vessels? 
What is a "leaky heart?" How may it be produced? 

13. What is the rate per minute of the heart beat? At 
the same rate, how many times will the heart beat in an 
hour? A week? A month? A year? 

14. What effect does muscular exercise have on the 
action of the heart? What is the danger following a 
period of training in athletics? How can this danger be 
avoided ? 

15. How is the heart itself nourished? 

16. How do arteries distribute blood to all parts of 
the body? Compare their distribution to a system for 
supplying a city with water. 

17. What are arterioles? How small are they? 

18. If an artery is cut, how would you know it? 

19. What is the difference in size between the smallest 
arterioles and capillaries into which they pour their 
blood? 



THE CIRCULATOEY SYSTEM 149 

20. What are capillaries! What is their function? 
How small are they ? With what are capillaries con- 
nected at each of their ends? 

21. What are veins? How large are they at their 
smallest beginnings? 

22. What is the function of the veins? What arrange- 
ment is made to keep the blood moving steadily toward 
the heart? What force keeps the blood flowing through 
the veins? 

23. If a vein is cut, how would you know it? 

24. Into what opening does the blood from all the 
veins empty? Why is the blood pumped to the lungs? 
Where does the blood go after it leaves the lungs and is 
returned to the left heart? 

25. What are the lymphatic vessels? What is their 
function ? 

26. What is lymph? What cells are always found in 
it? Why? 

27. What are the smallest of the lymphatic vessels 
called? How is lymph collected? Into what do they 
empty. Where ? 

28. What are lacteals? What is their function? 

29. What are lymph glands ? What is their chief func- 
tion? What is a "kernel?" What causes it? 



CHAPTER XIX 

BLOOD CELLS 

The Red Blood Cells are round in shape like a nickel 
but each side is hollowed out or concave, and are so small 
that about thirty-two hundred of them, placed side by side, 
would only measure one inch. They are about one-fourth 
as thick as their diameter. There are about five million 
of them in one average ' ' drop ' ' of blood. Millions of them 
are ' i worn out ' ' or destroyed every hour and new ones are 
manufactured to take their place. 

When the circulation in the capillaries brings them in 
close relation with the body cells, red corpuscles give up 
their oxygen and absorb carbon dioxide from the body 
cells. This process is spoken of as oxidation and the ex- 
change of the two gases (oxygen and carbon dioxide) is 
carried on by a process of osmosis. The red corpuscles in 
the capillaries of the lungs are separated from the air we 
breathe only by the thinest layer of cells, and there 
osmosis again occurs, and the red blood cells exchange their 
carbon dioxide for the life-giving oxygen. 

Oxidation in the tissue cells creates heat and it is this 
operation together with the exchange of food for cell 
wastes that keeps the body warm. 

The red color of blood is due to the coloring matter in 
the red blood corpuscles. Sometimes, as after a loss of 
blood from an injury, or a long period of wasting sickness, 
as typhoid fever, malaria or tuberculosis, these cells lose 
their coloring matter, or the blood loses too many of these 
cells. The body is said to be "pale." The lips,' finger 
nails and eyelids are not so rosy in color. This condi- 

150 



BLOOD CELLS 



151 



the 



the 




Figr. 63.— Showing- how white blood cells 
move about. A. At rest. B. Reaching 
out in two directions. C. Reaching in 
one direction. 



tion is known as anemia, and rest, good food and the at- 
tention of a competent doctor are needed. 

White Blood Cells are much larger than red blood cells 
and have the power of movement like an amoeba. In 
addition to their chief function of carrying food to 
body cells, they are the "policemen" of the body. 

If a disease germ finds its way into the tissues, 
white blood cell at 
once stops it, folds 
itself around it and 
digests or destroys it. 
If too many germs 
get into the tissues, 
hundreds of white 
blood cells collect 
around the invading 
enemy and seek to destroy them. A "boil" or "pimple" 
or simple "sore" is the battle ground of a fight between 
the common "pus" germs and the white blood cells. Such 
a condition is called 
an inflammation. 

If the white blood 
cells should win in 
their fight with the 
first attacking germs, 
there is very little in- 
flammation with its 
pain, redness, swell- 
ing and heat, and the tissues soon become normal or well. 

If the invading germs are large in numbers and strong 
in attack, nature sends a large number of white cells as 
1 ' reserves ' ' to keep the infection out of the blood. 

If the germs are the victors, the infection spreads 




Fig. 64.— Showing white blood cells di- 
gesting disease germs after "swallow- 
ing" them. 



152 PHYSIOLOGY, HYGIENE AND SANITATION 



through the lymphatics, where the lymphatic glands strive 
to check their advance. If the glands and their white cells 
win in this new battle area, the "kernels" soon become 
smaller and disappear; if the germs are again victorious, 
their poison is poured into the blood stream and one of the 
many forms of "blood poisoning" may develop. 

When the white blood cells are the victors in the con- 
flict with many of the germs which produce disease, the 

cells are so prepared and 
trained for fight, that, if 
such germs enter the body 
in later months or years, 
they are destroyed at once. 
This condition of the body 
is referred to as immun- 
ity. 

Vaccination against 
smallpox so trains the 
white blood cells that for 
many years afterwards a 
vaccinated person may 
live with a person having 
smallpox and never 
"take" it. 

An unvaccinated person would be almost certain, under 
the same circumstances, to contract the disease. Small- 
pox used to be as common as measles is now, and killed 
and disfigured its hundreds of thousands of victims. Now 
no one needs have this loathsome disease unless it is pre- 
ferred to a simple, harmless vaccination. 

Not a single case of smallpox occurred in the millions 
of soldiers of the Allies in the European War, because 
each of them had been vaccinated against it. 




Fig-. 65.— Red and five white blood 
corpuscles in inflammation. Note 
the relative increase of white 
cells. The white cells are the 
"reserves" brought into the fight 
against attacking germs. 



BLOOD CELLS 153 

An attack of diphtheria, scarlet fever, typhoid fever, 
measles, whooping cough, chickenpox, for a long time, 
usually, makes a person immune from later attacks. 

Typhoid fever can be prevented by the use of i ' typhoid 
vaccine. " The dead germs of typhoid fever are introduced 
under the skin through a hollow needle of a small syringe, 
and at once the white blood cells attack and destroy them. 

This operation is repeated, ten days apart, until the 
three inoculations have been given. A person so immun- 
ized is most certainly protected for a few years from an 
attack of typhoid fever. 











, z 


\^ 


f *•> : . 






A 




B 



Fig - . 66.— A. Smallpox vaccination. B. The scar. It is 
impossible for one so vaccinated to contract the dis- 
ease for many years. 

This disease in the Spanish- American "War killed more 
of our soldiers than were killed and wounded in the war. 
In the great European AVar, in which millions of men 
were living under conditions which favored the spread 
of this disease, typhoid fever was almost unknown be- 
cause every soldier was "immunized" against it. 

Malaria is a disease which results from the growth 
and reproduction of tiny parasites in the red blood cor- 
puscles. These parasites are introduced into the blood 



154 PHYSIOLOGY, HYGIENE AND SANITATION 




-aj aqj,— '2,9 'S\£. 
male mosquito 
which, if her- 
self infected, 
may give the 
disease to a 
person whom 
she ''bites." 



stream in the saliva of a female mosquito, of a certain 
species, when she " bites " or stings a person in search of 
blood for food. 

To be able to infect a person with ma- 
laria, she must have ' ' bitten, ' ' some days 
previously, a person who was a victim 
of malaria and her own body must have 
grown and reproduced the malarial par- 
asites. 

These parasites are stored in the saliv- 
ary glands of a mosquito. The "bill" 
of a mosquito is introduced through the 
skin of her victim and the saliva of the 
mosquito is used to dissolve the red blood 
corpuscles which are too large to be 
"sucked" through her bill. It is the acid saliva which 
causes her bite to sting and burn. 

The parasites, thus introduced, at once seek and enter 
red blood corpuscles to make their home. Iu a short time 

many new parasites are freed 
into the blood stream and in 
a few weeks millions of red 
blood corpuscles are thus de- 
stroyed. The victim becomes 
pale, weak and "thin" and 
unable to do hard labor. 

' ' Chills and fever ' ' are the 
common form of this dis- 
ease, although there are other 
forms of it in which the daily 

Fig-. 68.-The black dots are the << evprv of}™ Hav" chills 

malaria parasites which have 0I VYeiy Otnei Udy CIllllS 

grown in a red blood cell. A^ ^nf noour 

Many millions of cells may be uu - LLUL U ^ U1 - 

tack o f eS " r c°h y iii d s Sd n ?eve?." 4t - ^ * a serious disease and a 




BLOOD CELLS 155 

competent physician should be called, upon the appearance 
of such chills, who in addition to quinine or some similar 
drug, will give directions for the relief of the anemia and 
weakness and for protecting other members of the family 
or neighborhood from becoming infected. 

Summary 

Red blood corpuscles are one-fourth as thick as their 
diameter. By osmosis, oxygen is distributed to the body 
cells which by the same process convey their carbon 
dioxide to the red blood cells. In the lungs, carbon diox- 
ide is exchanged by osmosis for oxygen, and the blood is 
said, for this reason, to be " purified." 

Oxidation is "burning" of food with the exchange of 
oxygen for carbon dioxide in the tissues of the body. 

Anemia is the loss of coloring matter in the blood and 
may be caused by loss of a quantity of blood or by de- 
struction of red blood cells, as in a wasting disease. 

The white blood corpuscles, fewer in number and larger 
in size than the red blood cells, are the "defenders" of the 
body against certain pathogenic bacteria. Their chief 
function is to carry foofl to the body cells, in the lymph. 

They are present in large numbers when inflammation 
of tissues occurs, as in "boils," infected wounds, tonsilitis 
and like infections. 

"White blood cells are responsible for immunity against 
certain diseases. 

Typhoid fever does not usually attack one who has 
been a victim of it or who has been immunized against it. 

One may be "vaccinated" or immunized for typhoid 
fever at a small cost and it is a harmless procedure. 

Malaria is a disease caused by living organisms which 



156 PHYSIOLOGY, HYGIENE AND SANITATION 

destroy millions of red blood cells. It is carried only by 
the bite of certain mosquitoes, which are themselves in- 
fected. "Chills and fever" are the common name for 
this disease. It is curable and preventable. 

Questions 

1. What is the shape, size and number of red blood 
corpuscles? What becomes of them? 

2. What is their function? How is it performed? 

3. What is oxidation? What is meant by osmosis? 

4. What is oxidation in the tissues? 

5. What is anemia, and how may it be produced? How 
may one recognize an anemic person? 

6. Why are white blood cells sometimes called the 
"wandering cells?" 

7. What is their chief function ? What other important 
use have they? 

8. What is an inflammation? Give the symptoms, or 
signs, of an inflammation? Give three illustrations of an 
inflammation? 

9. What are normal tissues? 

10. Explain wlr> r "kernels" are produced. 

11. What is meant by "blood poisoning?" 

12. What is meant by immunity? Name five diseases 
which, after an attack, usually make one immune from 
subsequent attacks. 

13. What is the only way to prevent smallpox? How 
successful it is ? 

14. How do civilized governments keep typhoid fever 
from destroying their armies? How successful is this 
procedure ? 

15. What reason would you give for not being made 



BLOOD CELLS 157 

immune from an attack of smallpox or typhoid fever by 
vaccination ? 

16. What is malaria! How does one become infected 
with malaria? 

17. Why do mosquito bites "sting!" Why is it neces- 
sary for a mosquito to inject saliva into the body of a 
victim to secure its food! Under what conditions may a 
mosquito infect a person with malaria? 

18. Where do malarial parasites grow? How numer- 
ous may they become? 

19. What are the bad effects of malaria ? What are 
"chills and fever?" 

20. What should one do if malaria is present in the 
blood? 



CHAPTER XX 

HYGIENE OF THE CIRCULATION 

Exercise. The action of the muscles of the body helps 
to maintain the circulation of the blood and lymph. A 
person who takes no exercise has a poor circulation 
and a low vitality. Oxidation is imperfect and the 
body cells do not crave nourishment as they should in 
one who is most efficient. 

Such a person is usually pale, and will tire easily upon 
slight exertion. In sickness when reserve force is 
needed for recovery, a person who has failed to take 
proper exercise is much more apt to remain sick for a 
longer time, to be severely ill or die, than a person 
who is "physically fit' 7 by reason of proper daily ex- 
ercise. 

Too much , exercise, as in running, playing football, 
tennis, swimming or in any sports which require severe 
action of the muscles,, may cause an enlargement of the 
heart so that its valves do not perform their function 
properly, and a "leaky heart" may result. 

It is a good rule to stop hard exercise when one be- 
comes "tired." 

By careful training so that too great a strain is not 
placed upon the heart for too long a time, one may be- 
come accustomed to prolonged muscular exercise with 
no evil effects. In this case, the heart muscle becomes 
much thicker, larger and stronger. If one is compelled 
to retire to a quiet life, violent exercise should be grad- 
ually reduced so that the heart may adjust itself to the 
new condition. 

158 



HYGIENE OF THE CIRCULATION 159 

Fresh Air. Good health depends upon good blood, 
and one 's blood cannot be pure if the air that is breathed 
does not supply all the oxygen needed by the red blood 
cells. 

Expired air coming from the lungs, contains carbon 
dioxide collected from the body cells. If a room be 
small and tightly closed, this gas is re-breathed into the 
lungs, and the red blood corpuscles cannot get rid of 
all their new load of carbon dioxide, nor can they col- 
lect all the oxygen they need for the body cells. They 
are forced to make their trips through the body with a 
scant supply of oxygen for hungry cells, and hour after 
hour, the oxygen becomes less plentiful and the carbon 
dioxide more abundant. After several hours the body 
cells rebel at this sort of treatment and a " headache/ ' 
languid muscles, and a poor appetite voice their protest. 

Sleep with the windows open, winter and summer, 
and protect the body from cold with suitable clothing. 

Drugs for Headache. Many people think that a head- 
ache calls for a drug to relieve the pain. This is a mis- 
take, for most headache medicines are weakening to 
the heart muscle and they may do great harm by form- 
ing a drug habit. Most of the headaches are caused by 
disobeying such rules of health as sleeping in the fresh 
air, proper eating or attention to regular functions of 
the body in ridding itself of waste material. If these 
errors are corrected, headaches will usually disappear. 

Alcohol. The continued use of alcohol and whiskey, 
beer, wine or other alcoholic beverages, leads to serious 
results. 

The heart becomes enlarged because alcohol causes it 
to beat more rapidly. Its walls may become hardened 
and its force is reduced. 



160 PHYSIOLOGY, HYGIENE AND SANITATION 

The walls of the arteries usually become hardened and 
they refuse to expand and contract as they should do 
in health. This causes the heart to work harder to 
overcome the difficulty and a " leaky" heart may result. 

The capillaries become enlarged and more blood pours 
into them. This is shown by the "drunkard's nose," 
which is caused by a congestion of the skin capillaries. 

Blood vessels whose walls become hardened are more 
apt to burst or rupture than healthy ones, and apoplexy 
in heavy drinkers is common. This is a bursting of a 
blood vessel near the base of the brain with resulting 
paralysis. 

Drinkers usually become heavier and a large amount 
of fat collects in different parts of the body, especially 
the abdomen and the heart. The heart's action is im- 
paired for this reason. 

The blood cells are injured by the continued use of 
alcohol and oxidation and assimilation are imperfect so 
that the whole body suffers as a result. 

Hard drinkers usually have a great deal of difficulty 
in recovering from a disease which calls for a large re- 
serve force, as in pneumonia or typhoid fever. Their 
heart and arteries are much more apt to fail at the crit- 
ical turn of the disease. 

Tobacco acts as a stimulant to the heart, which causes 
it to beat quicker and somewhat irregularly. After 
continued indulgence in the use of this drug, a "tobacco 
heart" may result. This condition causes a rapid, ir- 
regular and hard beat of the heart, and the use of the 
drug should be gradually discontinued. Cigarette 
smoking by young people is especially harmful. 



HYGIENE OF THE CIRCULATION 161 

Summary- 
Exercise is of vital importance in maintaining the 
character and quality of the circulation of the blood and 
lymph, and for building up a reserve force for use in 
severe and prolonged sickness. 

Exercise may be overdone, by young people in their 
indulgence in sports. Moderation is the rule. 

Good blood depends largely on plenty of oxygen being 
supplied to it. "Bad air" causes a headache by the 
"air hunger" of the body cells. 

Indigestion, weakness and loss of vitality follow the 
continued habit of breathing air containing too much 
carbon dioxide. 

Headache medicines should be avoided, and habits of 
correct living employed instead. 

Alcohol, when its use is continued, has an injurious 
effect upon the heart, arteries, capillaries and blood 
cells. Vitality is lowered, heart disease is more likely 
to arise, apoplexy may follow the bursting of a blood 
vessel in the brain and inability to withstand the rav- 
ages of a severe illness are some of the consequences of 
the continued use of alcohol as a beverage. 

Tobacco unduly stimulates the heart and may lead to 
an irregular, hard, quick, wavering action of the heart, 
known as tobacco heart. This is common in young peo- 
ple who have foolishly formed a habit of smoking cig- 
arettes and "inhaling" the smoke. 

Questions 

1. What function do the muscles in action perform in 
relation to the circulation? 

2. "What is the effect of lack of exercise on the cir- 



162 PHYSIOLOGY, HYGIENE AND SANITATION 

dilation? What evil effect follows when proper exer- 
cise is not taken? 

3. What evil effects follow over-exercising? How 
may one over-exercise? What is a safe rule when ex- 
ercising ? 

4. If one has been in training for hard exercising, 
what danger is there if it is suddenly stopped? What 
rule should be followed if such a person retires to a quiet 
life? 

5. What is the relation of fresh air to good blood? 
What is a common effect of breathing "bad air?" Ex- 
plain how this is caused. 

6. What is the rule for sleeping, as it relates to air 
for the blood? 

7. Why should not drugs be taken to relieve head- 
aches? What are usually the best "headache remedies?" 

8. What is the effect on the heart of the continued 
indulgence in alcohol as a beverage? 

9. What evil effects does it have on the arteries? 

10. What effect has it on the capillaries? What is a 
"drunkard's nose?" 

11. What is apoplexy? What is a frequent cause? 

12. Who has the greater assurance of recovery from 
pneumonia or other severe illness, everything else being 
equal, the hard drinker or the person who does not use 
alcoholic liquor as a beverage? Why? 

13. What is the effect of tobacco on the heart? What 
is a tobacco heart? 

14. What are the evils of cigarette smoking by young 
people? Can you explain why "inhaling" cigarette 
smoke is most harmful? 



CHAPTER XXI 

THE RESPIRATORY SYSTEM 

Breathing is one of the first acts performed when one 
is born into the world. It ceases, as the soul passes into 
eternity. Without "breath/' we die. When one is seri- 
ously wounded, and is lying unconscious, one of the first 
things we look for is to see, if there is "breathing" or 
the act of respiration. If such a person is getting air into 
his lungs, there is life and, therefore, hope that recovery 
is possible. 

Digestion and absorption of food are vital operations, 
and so is the circulation of the blood and the lymph, but 
if air (oxygen) is not supplied to the blood for the body 
cells, all other operations of the body cease and death 
ensues. 

Object of Respiration. The purpose of respiration of 
air is to supply oxygen through the blood to the tissues 
of the body and to throw off the carbon dioxide from the 
body cells. 

The food carried to the body cells by the white blood 
cells is oxidized (burned) by the oxygen carried to them 
by the red blood cells. Light a match and watch the 
flame. This is oxidation of the carbon of the wood by 
the oxygen of the air. Heat and energy are produced. 
So it is within the tissues of the body ; the food is oxidized 
by the oxygen, and heat and energy are given to the body 
cells. 

If respiration stops, there may be plenty of cell food 
in the blood for the tissues, but with no oxygen present, 
the change of food into flesh, heat, and energy will not 

163 



164 PHYSIOLOGY, HYGIENE AND SANITATION 



occur. Oxygen is the agent necessary to cause the food 
to be oxidized (burned) within the cells. 

Respiration consists of two acts : inspiration and ex- 
piration. The air is taken into the lungs during inspira- 
tion, and it escapes from the lungs during expiration. 

Organs of Respiration. The organs of respiration are 
the lungs, air passages, the chest walls and the muscles 
that help in the act. 

The organs chiefly concerned in respiration are the 
lungs. In them the blood takes up oxygen and gives up 
its carbon dioxide. The air passages include the nostrils, 

the pharynx, the larynx, the 
trachea, the bronchioles and the 
air cells or sacs. 

The nostrils of the nose are 
well supplied with blood vessels 
and have a large surface of 
mucous membrane which is 
kept moist with a secretion of 
mucous. Hairs are found at the 
entrance into the nostrils. Dust 
and other impurities in the air 
are thus sifted and most often 
caught before they reach the lungs. Cold air is warmed 
in the nostrils ready for its use by the lungs. 

" Colds in the head" or "bad colds" are caused by 
the inhalation of certain germs that produce the disease. 
Sudden changes of temperature lower the resisting 
power of the mucous membrane of the nose to fight these 
invading germs, and a "bad cold" may result. Sitting 
or sleeping in a "draft" of air can only cause a cold if 
the body is not kept properly protected from cold by 
clothing, and it becomes suddenly chilled. 




Fig-. 69.— A typical adenoid 
face. A "mouth breather." 



THE RESPIRATORY SYSTEM 165 

The pharynx is the opening in the back of the throat 
from the outlet of the nostrils above the soft palate, to 
the entrance into the larynx at the top of the windpipe. 

The air passing through this space is warmed and 
further relieved of its impurities. 

In the upper and on the back wall of the pharynx are 
sometimes found enlarged adenoids. These are spongy 
growths of loose tissue which may so obstruct the flow 
of air through the nose, as to force a person having 
adenoids, to breathe through the mouth. If this tissue 
is not removed, it may lead to serious consequences such 
as earache, defective hearing and anemia. The whole 
facial expression may be changed and the features be 
permanently deformed. 

Adenoids are easily removed by a skilled surgeon and 
the operation is quite simple and almost free from danger, 
and should be done. 

The tonsils are located in the pharynx on each side in 
front and below the outer margins of the soft palate. 

The function of the tonsils is to filter material enter- 
ing the lymphatics from the mouth, nose and pharynx, 
so that infectious matter may not enter the blood. 

Often they become infected and enlarged. An in- 
flammation of the tonsils is called tonsilitis. If the trouble 
persists and the tonsils become so large that they inter- 
fere with breathing, or cause earache or defective hear- 
ing or anemia, they should be removed by a competent 
surgeon. 

The Larynx. The air after passing through the nostrils 
and pharynx enters the larynx, which is located at the 
top of the windpipe. 

The voice is produced in this organ as the air passes 
out through the opening (glottis) at the top of the larynx 



166 PHYSIOLOGY, HYGIENE AND SANITATION 




Fig-. 70.— A. Showing- the 
location of tonsil and 
its connection with the 
lymphatics. 



The vocal cords are not really cords but membranes which, 
by contraction of muscles, are made to close partly the 

glottis. The air forced between 
these " cords " causes them to vi- 
brate and sound is produced. 
These sounds are regulated by 
control of the muscles and the 
voice is modulated or changed at 
will. 

The larynx has been well called 
the " voice-box." 

The "Adam's Apple " is a pro- 
jection in the front of the throat 
of part of the larynx. 

Food and drink when swallow- 
ed must pass over the opening 
into the larynx. The epiglottis 
promptly closes this opening and the material is passed 
safely over the glottis. When it fails to operate 

promptly a bit of food or drink 
may be sucked into the larynx and 
at once there is violent coughing 
to force it out. 

The trachea, or windpipe, is a 
tube about one inch in diameter 
and about four and one-half 
inches long. It begins at the lower 
end of the larynx and ends in two 
branches, the right and left 
bronchi. It is kept from closing 
by horseshoe-shape rings of car- 
Fig-. 71.— b. Diphtheria at- tillage which do not quite com- 

tacking the tonsils which . 

are covered with a tough plete the ring at the rear side. 

membrane. . . 

The bronchi continue to divide 




THE RESPIRATORY SYSTEM 167 

like the branching of a tree, and such branches, begin- 
ning in the lung, are called bronchial tubes. The bron- 
chial tubes further subdivide, and terminate in the air- 
sacs or cells of the lungs. 

Summary 

Respiration, consisting of the acts of inspiration and 
expiration, is one of the vital operations for maintaining 
life. 

Its object is to furnish oxygen through the blood for 
the burning of food in the body cells and to rid the blood 
of its carbon dioxide. 

The lungs, air pasages, walls of the chest and certain 
muscles are the organs of respiration. 

The nose and pharynx filter and warm the inspired 
air. Adenoids and enlarged tonsils, when they interfere 
with respiration, should be removed. 

The larynx is the organ of speech and is part of the 
air passages. 

Voice is a sound made by the forced passage of air 
through the vocal cords, during expiration, which are 
made to vibrate by the action of controlling muscles. 

The trachea is the windpipe and divides into two 
bronchi which, in turn, divide into bronchial tubes. Air 
sa^s are the most distant division of the air passages. 

Questions 

1. What is one of the first and last acts performed by 
the human body? 

2. What is the result, if one stop breathing? Why? 

3. What are the two chief functions of respiration? 

4. What is meant by oxidation of food in the body 



168 PHYSIOLOGY, HYGIENE AND SANITATION 

cells? What agent is necessary for this to be done? Is 
there any relation between the burning of coal and oxida- 
tion in the tissues? "What is it? 

5. What is inspiration? Expiration? 

6. Name the organs of respiration. What is the chief 
one? 

7. What two functions of respiration have the nostrils ? 
What is a "bad cold?" 

8. What is the pharynx? What are its functions? 
What are adenoids? What harm may they do? What is 
the function of the tonsils? When should they be re- 
moved? 

9. What is the larynx? What other name has some- 
times been given it? What is the glottis? The epigottis? 
How may one become "strangled" on food or water? 

10. What is voice? How is it produced? How is it 
regulated? What is the difference between a song that 
is sung and a scream? An ordinary conversation? What 
is the "Adam's Apple?" 

11. What is the trachea? What is its length and 
diameter? 

12. What are the bronchi ? How many bronchi ? What 
are the bronchial tubes? Into what do these terminate? 



CHAPTER XXII 

THE LUNGS 



The chief function of the air passages, the walls of the 
chest and the muscles of respiration, is to keep a flow of 
air into the lungs and out of them. 
The lungs are two 
in number, the 
right and the left. 
They occupy most 
of the space in the 
chest and weigh 
about three 
pounds. 

The right lung 
is slightly larger 
and heavier than 
the left lung. Each 
lung is separated 
into sections o r 
lobes. The right 
lung has three 
lobes and the left 
one has two lobes. 

The division of the lung is one of nature 's provisions to 
prevent such diseases as tuberculosis (consumption) and 
pneumonia from destroying or impairing a whole lung, 
when one part of it becomes infected. 

Lungs are commonly called "lights" in animals killed for 
food, probably because lung tissue, under such circum- 

169 




Fi§\ 72.— The lungs. A. Right lung. B. 
Left lung. C. The pericardium containing 
the heart. 



170 PHYSIOLOGY, HYGIENE AND SANITATION 



stances, is filled with air and is so "light" that it floats in 

water. 

The lungs are penetrated in every direction by the bron- 
chial tubes, which branch from each bronchus, like the 

branches of a tree. 
These tubes finally become so small that their branches 

may be likened to the twigs of a tree that send forth stems ; 

and finally they end in the air sacs of the lungs. These air 

sacs are so 
small that 
about five 
mill ion of 
them would 
be found in a 
pair of lungs, 
and if their 
walls could 
be spread out 
on a flat sur- 
face and 
placed to- 
gether as in a 
"crazy quilt" 
or bed cover, 
their surface 
would be as 

large as a rug four feet wide and five feet long, or twenty 

square feet. 

It is in the air sacs that the exchange of oxygen and 

carbon dioxide is made. 

The lungs are covered with a smooth, velvety lining or 

cover called the pleura. The pleura also winds around 

and covers the inside surface of the chest walls. 




Fig\ 73.— Showing- the Trachea, A. Rig-ht bron- 
chus, B. Left bronchus, C. and bronchial 
tubes as they subdivide from each bronchus. 
Note the ring's of cartillagre (gristle) in the larg-- 
est tubes. 



THE LUNGS 



171 



The space formed by the ribs and breast bone (the 
sternum) in front, and the upper part of the "backbone" 
(spinal column) behind, is called the "thoracic cavity " 
and a cage or frame forming its walls is called the thorax. 

The thoracic cavity is mostly occupied by the lungs and 
the heart. 

The outer walls of the lungs lie in close contact with 
the inner walls of the thoracic cavity. The layers of 
pleura are, therefore, in contact and as the walls move to 
and fro, in breathing, the layers of pleura rub over one 
another. Nature pro- 
vides a fluid to pre- 
vent friction and ir- 
ritation of the pleura. 

If an infection of 
the pleura occur, 
such an inflamma- 
tion resulting is call- 
ed pleurisy, and is 
exceedingly painful, 
because, with each 
respiration, the sen- 
sitive nerves are rubbed together. 

How We Breathe. Force all of the air out of the lungs 
and hold "your breath " until you are forced to breathe. 
Notice what happens. The walls of the chest are raised and 
spread out ; the back is straightened ; the nostrils are opened 
a little wider, and something seems to "swell up inside." 

The muscles between and overlying the ribs, raise the 
drooping ribs. A broad muscle, arched across the lower out- 
let of the thorax (diaghragm), is made to contract which 
pushes the stomach and bowels downward and this further 




A B 

Fig*. 74.— A. The chest in expiration. B. 
The chest in inspiration. Note its in- 
creased capacity. 



172 PHYSIOLOGY, HYGIENE AND SANITATION 

increases the space in the thorax. The lungs are made to 
follow the walls of the thorax, as more space is thus created, 
and the air rushes through the nostrils into the lungs 
exactly as it does into a bottle when the cork is suddenly 
pulled. 

Now after drawing a full breath, hold it until you are 
forced to "let go." Notice what happens. The chest walls 
fall, the stomach and bowels seem to rise, the shoulders and 
back relax a little. The lungs which, when full of air were 
' ' on the stretch ' ' like a piece of elastic rubber, now contract 
and the air comes rushing out of the nostrils, with a slight 
breezy sound. This is the act of expiration. 

The Capacity of the Lungs. One wonders how much air 
the lungs will hold. In ordinary, quiet breathing only 
about thirty cubic inches of air pass into the lungs. In a 
forced respiration about one-hundred and thirty cubic 
inches of air can be inhaled and two hundred and thirty 
cubic inches or about one gallon can be exhaled. There 
always remains in the lungs between "breaths" about one- 
hundred cubic inches of air as a reserve supply for the 
blood during the intervals in the act of respiration. The 
total capacity of an average lung is about three-hundred 
and thirty cubic inches of air or less than one and one-half 
gallons. 

Rate of Breathing. The average adult at rest breathes 
about eighteen times every minute ; during and after vio- 
lent exercise, the rate is much more rapid and the amount 
of air inhaled each time is increased, because the increased 
energy of the body calls for more oxygen to burn cells to 
produce heat and energy. 



THE LUNGS 173 

Summary 

The lungs, two in number, are divided into lobes and are 
penetrated throughout by the bronchial tubes, which have 
their ending in the air sacs, where osmosis of carbon dioxide 
and oxygen occurs. 

The pleura lines the surface of the lungs and the inner 
surface of the thorax. 

Inspiration is performed by the action of the muscles 
which increase the capacity of the thorax by elevating the 
chest walls and depressing the diaphragm. 

Expiration is performed by the contraction of the 
stretched elastic tissues of the lungs, w r hen the muscles of 
the chest walls and the diaphragm are allowed to relax. 

The rate of breathing and the amount of air breathed 
depend upon age, state of health, the employment, and 
habits of the individual. 

Questions 

1. What organs cause the air to enter the lungs and 
escape from them? 

2. How many lungs has a person ? What are they called ? 
Where are the lungs situated? 

3. What is the average weight of the lungs? 

4. What are the lobes of the lungs ? How many lobes in 
each lung ? What is one reason for having lobes in lungs ? 
What are "lights"? 

5. Why does lung tissue, when it is cut across, look as if 
it were full of holes ? Why are they of so many different 
sizes ? 

6. What are air cells? Where are they? How small are 
they? What would be their total area of surface if their 
walls were spread out in one sheet ? 

180 



174 PHYSIOLOGY, HYGIENE AND SANITATION 

7. What takes place in the air cells of the lungs ? 

8. What is the pleura? Where is it? What is pleurisy? 
Why does not the rubbing together of the layers of the 
pleura cause pain in health? Why is there pain in 
pleurisy ? 

9. Name five things observed in a forced inspiration. 
Explain why these things occur. 

10. Name five things observed when the air is expired. 
What is the cause of the air rushing out of the lungs dur- 
ing expiration? 

11. How much air is breathed in ordinary respiration? 
How much may one, by effort, inhale? How much air re- 
mains at all times in the lungs ? Why ? 

12. How many times a minute does a man ordinarily 
breathe? When is there faster breathing? Why? Can 
you explain why a sickness with fever causes a more rapid 
breathing? Why does a person become "thinner" during 
such illness ? 



CHAPTER XXIII 

AIR 

Composition of Air. Air is a mixture of gases, which 
may be separated from one another. It differs from a 
chemical compound like water, which is made up of two 
parts of hydrogen and one part of oxygen. These two 
gases, when mixed, form a new substance which is a 
fluid. 

Air is composed, in the main, of nitrogen and oxygen, 
in the proportion of about four parts of the former to 
one of the latter. Carbon dioxide is present in about 
one-thirtieth of one per cent in pure air. Oxygen is 
easily extracted from air. 

Place a tumbler over a candle, floating in water; light 
the candle and invert the glass over it until the edges 
of the glass touch the water. The flame burns all the 
oxygen in the glass; and the candle "goes out." Water 
is forced up into the glass and it will be noticed that 
the water fills it about one-fifth full to take the place of 
the oxygen. 

Air Pressure. Air completely surrounds the earth and 
extends hundreds of miles toward the sky. Being a gas 
it has weight and on the earth, at the sea level, its 
pressure is near fourteen pounds to the square inch. On 
high mountain tops it is less, and at the great heights 
to which aviators ascend, the pressure is so much lighter 
that they frequently suffer great headaches or even faint. 
This is because man is constructed to live where the air 
pressure is great. 

Air pressure can be demonstrated many ways. The 
sound made when water is poured out of a jug is made by 
the air pushing its way through the w&t§r to fill the space 

175 



176 PHYSIOLOGY, HYGIENE AND SANITATION 

that had just been occupied by water. The noise made 
by clapping the hands is produced by the air suddenly 
rushing in to fill the space made vacant by the sudden 
impact of the flat surfaces of the hand. The sound of 
thunder is made in a similar manner when lightning cre- 
ates a vacuum or vacant area in the air. 

The sound of breathing in inspiration in made by the 
inward rush of air to fill the vacuum that is made within 
the lung cells. The muscles of the thoracic cavity cre- 
ate a vacuum by enlarging the space which is filled by 
the lungs. The air pressure forces the lung to follow 
the expanding walls. If there were a large opening made 
through the ribs and pleura so that air might rush 
through this new opening as the ribs move outward, 
the lung would not expand and inspiration would be 
impossible. 

Nitrogen comprises about four-fifths of the air. It 
is of no value when breathed except to dilute the oxy- 
gen needed in the body cells. Man cannot breathe pure 
oxygen and live long. 

Carbon Dioxide is a gas found in small quantities in 
the air. It is a plant food. 

Every process of oxidation, whether in the roaring 
furnaces or in the silent oxidation within the tissues of 
all air-breathing animals, supplies to the air carbon 
dioxide. 

A man in every hour will exhale about seven gallons ' 
of carbon dioxide ; a ton of coal, when burned, will pro- 
duce about nine thousand barrels of this gas. The plants 
absorb this gas and use it for food, thereby producing 
starch, and as they work they give off our life-saving 
oxygen. Thus again do we see the intimate working re- 
lation between the animal and vegetable life, for not 



AIR 177 

only do plants help to furnish our food but while doing 
so purify and replenish our air supply. 

Changes in Inspired Air. Air is warmed in its jour- 
ney through the nostrils and air passages. 

Upon reaching the air-sacs, it is separated by the cir- 
culating blood stream only by a single layer of cells. 
The red blood cells, laden with carbon dioxide from 
burned tissue cells, now give up this gas and receive 
in return the life-giving oxygen. The air also receives 
moisture or water. This may be proven by blowing 
the breath upon a cold mirror w T hen the vapor is con- 
densed and may be seen as water. 

Inspired air contains a little less than four parts of 
carbon dioxide to ten thousand parts of air. Expired 
air contains about four hundred and thirty parts of 
carbon dioxide to the ten thousand parts of such air. 
Inspired air contains about twenty per cent oxygen. 
Expired air contains about fifteen per cent oxygen. The 
body needs can be maintained, if the supply of oxygen 
is about ten per cent so that air may be breathed twice 
without harm to the body. 

Effect of Breathing Air With Insufficient Oxygen. 
Rebreathing the same air results in an increased amount 
of carbon dioxide, and causes one to become drowsy 
and mentally dull. 

Children at school and persons at church get drowsy 
and inattentive, many times, because the air in the 
room has become too heavily laden with carbon dioxide. 

Long continued living in rooms which permit the ac- 
cumulation of this gas causes anemia, and general ill 
health with loss of efficiency. 

A room is " close" or contains too much carbon diox- 
ide if, when entering it from the pure air, it has a bad 
odor and a kind of "stuffy" feeling. The nose is a good 
agent to detect bad air. 



178 PHYSIOLOGY, HYGIENE AND SANITATION 

Summary- 
Air, a mixture and not a compound, is composed 
mainly of oxygen and nitrogen in the ratio of one to four. 
Inspiration is possible because of air pressure, which 
at the sea level is about fourteen pounds to the square 
inch. Nitrogen is inert and dilutes the oxygen so that 
the body cells may best use it. 

Carbon dioxide is a product of combustion, or oxida- 
tion, and is a plant food for making starches. 

Inspired air is warmed, moistened, filtered, and loses 
oxygen and gains carbon dioxide. Air rebreathed many 
times produces heaviness, weakness and mental dull- 
ness. 

Questions 

1. Explain that air is a mixture of gases and not a 
chemical compound. 

2. Give an example of a chemical compound and tell 
its composition. 

3. Of what is air composed chiefly? In what propor- 
tion are the gases formed? 

4. How can the relative amount of gases be shown 
to exist in air? 

5. "Where is air found 2 How much does air weigh at 
the sea shore? 

6. "What difference is there in its weight, three miles 
high? How do great altitudes affect aviators at times? 

7. Name three acts which demonstrate air pressure. 
What is a vacuum? 

8. Why does air enter the lungs when the walls of the 
thorax are lifted by the muscles of inspiration? Which 



AIR 179 

exerts the stronger force in this act, the air pressure or 
elastic lung tissue? Why? 

9. What is the use of nitrogen in respiration? 

10. What is carbon dioxide? How is it produced? How 
much will a man produce every hour? How many days 
would he have to live to oxidize as much material in his 
bod}^ cells as is represented in a ton of coal burned? 

11. How are starches in plants made? What gas is 
given off when starch is thus produced? 

12. Describe what is meant by the ''intimate working 
relation between the animal and vegetable life?" 

13. Name four changes that occur in inspired air. 

14. How many parts of carbon dioxide in ten thousand 
of air does inspired air gain during inspiration? How 
many per cent of oxygen does air lose, during respira- 
tion? What is the lowest per cent of oxygen which air 
may contain and be sufficiently pure to meet the body's 
needs? 

15. What is the effect on the body of rebreathing the 
same air? What effect on the mind? Why do people 
sometimes "go to sleep in church?" 

16. What organ of the body makes a good detective 
to discover air with too much carbon dioxide? What 
does it discover in such air usually? 



CHAPTER XXIV 



VENTILATION 




Quantity of Air Needed. An average man who is not 
engaged at physical labor requires about 3,000 cubic feet 
of fresh air every hour; a child of twelve about one- 
half as much. 

School houses and public buildings should contain 600 
cubic feet of space for each person who occupies them. 

During the heated months 
an abundance of fresh air is 
admitted through the doors 
and windows of most houses. 
In cold weather windows and 
doors are kept tightly closed 
to keep a room or build- 
ing heated for protection 
against cold. People living 
in such places are often com- 
pelled to breathe and rebreathe the same air w^hich soon 
becomes laden with carbon dioxide and bad odors. Some 
means of ventilation must be provided. 

Ventilation is a process by which impure air may be re- 
moved from closed places and fresh air be made to take 
its place. 

Methods of Ventilation. In modern churches, large 
school buildings and office buildings, a ventilating sys- 
tem is usually installed. By means of revolving fans fresh 
air, heated or cooled to the proper temperature of 68° F. 
is forced through large pipes into each room and another 
set of pipes is made to take stale air out of each room. 



Fig-. 75.— Showing- imperfect 
distribution of air when the 
inlet for fresh air is on the 
floor line and the outlet is at 
the ceiling- farthest away. 



VENTILATION 



181 





_ 






* > ;r 


is 


1 




— /' ; 




\ 




{H* 2 ™ 


.; 






J W^ 


1 


\ 




u .j^^Z-J | 




|yt=^ 









The simplest method of ven- 
tilation is by the raising and 
lowering of windows in a room. 
Warm air, being lighter than 
cold air, will rise and if the 
air outside of the room is colder 
than the air inside, the warm 
air passes out of the windows 
at their top and cold air comes 
in below. 

In winter time the rush of 
cold air into a room creates a 
draft and persons sitting too 
close to it may become cooled 
too suddenly. To overcome this, 
a board may be placed at an 
angle on the bottom of the 
window which will direct the 
flow of air upwards where it 
mixes with the warmer air of the room, or a board may 
be placed under the raised sash to close the entire space 
and the cold air allowed to enter the room only between 
the upper and lower sashes. 

School Room Ventilation, 
school houses the archi- 
tect usually includes in his 
plans a provision for the 
proper heating and ven- 
tilation of the building. 
Fresh air ducts and in- 
lets for each room and 
foul air outlets from each Fig \^ ^--showing- defective 

method of ventilation by plae- 

room are made to operate so \ ns the ^ air inlet midway be- 

r tween floor and ceiling- and 

that an even temperature outlet at ceiling- at opposite 

r end of room. 



Pig-. 76.— A means of venti- 
lating in cold weather by 
lowering the top sash and 
raising the lower one and 
placing- a board in the 
opening below the lower 
sash. 



In large, properly built 




182 PHYSIOLOGY, HYGIENE AND SANITATION 



and a plentiful supply of pure air are furnished con- 
stantly. 

The air in small school rooms, heated by stoves, fre- 
quently becomes very warm and foul when the windows 
are tightly closed. A steel jacket may be placed entirely 
around the stove leaving several inches of space and 
fresh air may be conveyed through a pipe from outside 

the building to the inside 
of the jacket below the 
fire-bowl. 

Air entering this pipe is 
at once heated as it rises 
and it is mixed with the 
air in the room as it 
escapes from the top of 
the jacket. Another large 
pipe is arranged to con- 
nect with the chimney to 
carry foul air out of the 
room. Its lower end should 
rest on legs fastened 
to the floor near the chim- 
ney. Its upper end should 
be inserted in a drum or 

Fte. 78.-Illu S trating the method of J acket which fitS int0 a 

Jp*Ja \i?Tuc7s Uh a st ° ve " hole in the chimney which 

is a few inches larger than 
the smoke pipe from the stove. The smoke or stove pipe 
should run through this drum into the chimney. 

The foul air which settles to the floor would thus be 
drawn through this pipe by the rising heat and smoke 
in the chimney from the stove pipe and escape with it. 

If a school room is not provided with some arrange- 




VENTILATION 



183 



ment for its proper ventilation, frequent recesses should 
be given and for a few minutes windows and doors should 
be opened wide to admit an abundance of fresh air. 

A sensible method to ventilate such a school room is 
to open every window and have the doors swung vio- 
lently to and fro. The pupils during this period should 
stand in their places at the desks and engage in some 
simple stretching exercises of their muscles. Fresh air 
would quickly enter in abundance and any danger from 
drafts would be overcome by the stimulation of the cir- 
culation by the exercises. 



-v ; 




mmm<***°~~~J 



WSfP 



Fig-. 79.— Showing- the imperfect 
distribution of fresh air 
when the inlet and outlet are 
placed at the floor on op- 
posite sides of the room. 




Fig. 80.— Showing the best way 
of ventilating by placing the 
inlet midway between the 
ceiling and floor and the out- 
let at the same end of the 
room near the floor. 



Many times pupils who are dull and listless because 
of the foul air in a close room become at once alert and 
perform their duties much better. 

The sloping board may be employed in many school 
rooms, and the upper sashes should be lowered a few 
inches. In extremely cold weather it may be necessary 
to close the space above the upper sash and use only the 
tight-fitting board below the lower sash. 

In very cold weather, air enters in good quantities 
through cracks in walls and around windows and doors. 

Sleeping Room Ventilation. People have begun to 



184 PHYSIOLOGY, HYGIENE AND SANITATION 

learn that fresh air, like pure water, is one of nature's 
richest blessings to maintain health and prevent disease, 
and that both are free for their seeking. For many years, 




Fig-. 81.— An outdoor sleeping- porch connected by a stairway to a 
down-stairs living room, screened and protected by an over-hang- 
ing roof from sun and driving rains. The six-foot elevation and 
the wainscoting protect a female occupant from fear of intruders. 
The screen on hinges at the left side allows bed clothing to be 
sunned and "aired." The space below the wainscoting prevents 
the collection of carbon dioxide gas and insures a free circulation 
of air. In extremely cold weather or in a driving rain or a drift- 
ing snow, curtains may be placed around part of the porch. The 
cost of such a porch need not exceed $25.00. 



it was taught that " night air" was dangerous and one 
was more liable to be ill if sleeping was done in night air. 
Now we know that to sleep out-of-doors at night, prop- 



VENTILATION 185 

erly screened from mosquitoes and protected from cold, 
is the ideal way to furnish the body cells with oxygen 
while the body is resting and being rebuilt after the 
day's work. 

Sleeping Porches are now being built in nearly every 
modern home. An upper porch connecting with bed 
rooms is so constructed that there is privacy; flies, mos- 
quitoes, and insects are excluded by screening. In cold 
weather, one may undress and prepare for sleeping in 
a warm living room and enter the sleeping porch through 
a window or door. A woolen helmet is worn over the 
head and ears and around the neck, leaving an open 
space for the eyes, nose, and mouth. 

Woolen blankets are tucked about the bed so that cold 
cannot enter and one may sleep in comfort in the coldest 
weather. Children and "weakly" people may need hot 
water jugs or "pigs" filled with hot water, placed under 
the blankets near the feet to help keep the body warm. 

If a sleeping porch cannot be used, the windows in 
the sleeping room should be opened, winter and sum- 
mer, to permit plenty of fresh air to enter. 

Summary 

The quantity and quality of air for the body is as im- 
portant a matter as the quantity and quality of food. 

Ventilation is a method employed to furnish enclosed 
spaces with fresh air and remove the foul air. In large 
modern buildings, ventilation is done by means of fresh 
and foul air ducts through which air is forced by revolv- 
ing fans. 

In cold weather, the flowing of currents of air by reason 
of the difference in temperature is the ordinary and sim- 



186 PHYSIOLOGY, HYGIENE AND SANITATION 

pie method of ventilating homes, small school houses, 
and the smaller public meeting places. 

A jacketed stove with a fresh air intake and a foul 
air outlet is a fairly good means of ventilating small 
school houses. 

Windows should be raised and lowered for free cir- 
culation of air when the weather permits. Sloping win- 
dow boards can be used in cold weather to prevent drafts 
when fresh air is admitted through windows. 

Fresh air during the period of sleeping is vitally im- 
portant. Sleeping porches, properly screened and ad- 
joining a warm living room, are ideal for winter and 
summer use. 

Questions 

1. How many gallons of fresh air does an average man 
require every hour, if he is not doing hard labor? How 
many cubic feet does a boy of twelve years need every 
hour? 

2. If your school room, inside, is thirty feet long, 
twenty feet wide and ten feet high, how many pupils 
may live in it, giving to each six hundred cubic feet of 
space? If sixty pupils are in a room ten feet high, and 
sixty feet long, how wide must it be to give each pupil 
the proper amount of space? 

3. When is there most difficulty in furnishing plenty of 
air? Why? 

4. What is ventilation? 

5. How are properly built, large office buildings and 
school houses ventilated? 

6. What is the simpliest way to ventilate a room? 

7. Why does warm air rise? On a summer day when 



VENTILATION 187 

no breeze is blowing, if a window in a school room is 
raised, will the air rush in the open window? Why? 

8. How would you arrange to permit fresh air to 
enter through a window in cold weather so that a draft 
might not blow on persons sitting near by? 

9. How may a small school room be ventilated with a 
stove-jacket? Why should the fresh air inlet be placed 
below the fire bowl of the stove? Why should the foul 
air outlet pipe extend nearly to the floor? Why could it 
not run out of the room through the wall instead of the 
chimney? What is the reason for this pipe running into 
a drum through which the stove smoke-pipe runs? 

10. If a school room has no provision for ventilation, 
how should fresh air be supplied? What is the advantage 
of swinging doors in attempting to ventilate a room? 
If pupils are not given a recess, why could they not sit 
still in their seats while windows and doors are open to 
admit fresh air? What are the advantages of exercising 
while ventilation is being done? 

11. What is the difference between " night air" and 
"day air"? Is night air healthy? Why? Where should 
one sleep? Where should sleeping porches be built? 
Why? Why should they be screened? How may one 
sleep "out-of-doors" in a sleeping porch and keep warm? 

12. How should the sleeping room be ventilated? Dur- 
ing what seasons of the year should sleeping porches be 
used? Why? 



CHAPTER XXV 

HYGIENE OF THE RESPIRATORY SYSTEM 

Dust in Air. Nature has made wise provisions for keep- 
ing particles of dust and like impurities from reaching the 
delicate walls of the air-sacs. The hairs and the coating of 
mucous in the nose, the winding passages through the air 
ducts leading to the lungs, catch most of the dust. 

The bronchi, and the bronchial tubes are lined inside 
with mucous membrane, on the surface of which and pro- 
jecting into the air passages, are tiny waving arms (cilia) 
which always direct their motion towards the mouth. 
Under the microscope these cilia remind one of a waving 
field of wheat and tiny particles are seen being pushed 
along as if they were directed by reason. 

The function of cilia is to clear the air passages of dust, 
germs and other foreign matter. 

Dust is nearly always present in the air. A stream of 
sunshine in a darkened room reveals thousands of particles 
of dust. 

In dry seasons, dust becomes abundant in the air. 

In certain trades, as stone cutting, dressing lumber, work- 
ing in cotton mills, a great deal of dust is always present 
in the air where people are employed. They should wear 
protectors over the nose and mouth, which are so made that 
all the inspired air has been sifted and almost freed from 
dust. 

Housewives or others who sweep homes and public build- 
ings should avoid "making a dust" while they "clean" 
the rooms. 

A vacuum cleaner, which sucks the dust from the floor, 

188 



HYGIENE OF THE RESPIRATORY SYSTEM 189 



is the best means of removing the dust. A "carpet 
sweeper" is excellent, for the dust is immediately gathered 
into a dust-proof box which is part of the machine. 

Oiled sawdust, or wet bits of paper, strewn over the floor 
and swept up gently may be used to avoid dust. 

The use of a dry broom on dry floors is very objection- 
able, and dust, instead of being removed from the room, 
is scattered largely over tables, chairs, books, and else- 
where about the room. 

"Dusting" a room should be done with a soft cloth 
wrung out of hot water to which a 
little "coal oil" has been added. 

Rooms occupied by a person ill of 
tuberculosis, influenza, diphtheria 
and like diseases should never be 
swept with a dry broom. 

Street dust in cities is dangerous 
for it is more apt to contain certain 
germs that can produce disease. 

Gases in the Air. Air often is 
mixed with coal smoke, especially, in 
manufacturing centers. This is in- 
jurious to the lungs and general health because such air 
may contain the gases of coal and are absorbed with oxygen 
into the blood cells. 

Many modern cities now require all coal-burning fact- 
ories to use "smoke consumers." 

Certain trades, as in the manufacture of chemicals, 
matches, etc., expose the workers to noxious or poisonous 
gases. Masks should be provided and their use made com- 
pulsory to protect the delicate air-cells and to prevent the 
absorption of such gases into the blood. 

Sewer gas often escapes from defective plumbing into 




Fig-. 82.— Colonies of 
germs grown on 
gelatin in a saucer 
which had been ex- 
posed to street dust 
for half an hour. 



190 PHYSIOLOGY, HYGIENE AND SANITATION 

living rooms and offices. Not only is it disagreeable to the 
sense of smell, but such gases, when breathed for some 
days or weeks, may cause serious changes in the quality of 
the blood with resulting loss of weight, anemia and loss of 
energy. 

Exercise and Air. Exercise of the body muscles quick- 
ens the action of the heart, which pumps with more force; 
the blood circulates more rapidly; body cells burn more 
oxygen and heat and energy are increased. The breathing 
is fuller and more rapid to supply enough oxygen to meet 
the increased demand of the cells. 




Fig 



-Showing stretching- exercises that may be 
taken upon rising- in the morning-. 



Exercise should be taken in the open air to get the most 
benefit from it. The outdoor sports are of great value for 
this reason. 

Upon rising in the morning, the muscles of the arms, 
chest, legs, and abdomen should be exercised for ten minutes 
by stretching, bending, squatting, turning and lifting mo- 
tions. The windows should be opened wide. 

Tight Clothing about the waist or chest is to be avoided, 
because it interferes with deep breathing and permits a too 
limited supply of air for the blood cells. 



HYGIENE OF THE RESPIRATORY SYSTEM 191 



Tight corsets are doubly injurious because not only are 
the lungs compressed and the air supply decreased, but the 
circulation of the blood through the digestive organs is 
hindered and it interferes with the important duty of 
nature for relieving the body of its wastes. 

Postures. The lungs operate best when the chest is not 
restricted in its movements. One should walk erect with 
the back straightened and the shoulders thrown back and 
head erect. This allows free movements of the chest during 
respiration. When sitting at a desk, 
the back should not be curved and the 
shoulders allowed to droop. The seat of 
the desk should not be too high or too 
low. 

School desks should be so constructed 
that the desk may be changed to fit the 
child, and not of one size and rigid, so 
that the child may be grown crooked to 
fit the desk. 

During sleep, the head should not be 
raised too high by the use of pillows. 
The body should be kept as nearly as 
possible in its normal line. 

Alcohol weakens the resisting power 
of the body to disease. Some of the alcohol that is taken 
into the body cannot be oxidized and is thrown out of 
the body through the lungs as a vapor. The odor of 
whiskey can be smelled "on the breath" of one who has 
taken too much whiskey. 

Habitual drinkers are particularly liable to colds, la 
grippe and pneumonia. 

The death rate from pneumonia among those who drink 
to excess is very much higher than in abstainers. 




Fig". 84.— Squat- 
ting exercise to 
exercise mus- 
cles of leg- and 
back. 



192 PHYSIOLOGY, HYGIENE AND SANITATION 

It was a common belief that whiskey was good for colds 
and la grippe, and that its use would prevent snch diseases. 
This made a very good excuse for people who craved 
alcohol, but it has no truth in it. 

By lowering the resistance of the body cells, it may in- 
crease one's chances of becoming ill of these and other 
diseases. 

Tobacco. Tobacco smoke is irritating to the delicate 
mucous membrane of the air pass- 
ages and, for this reason, sore 
throat, hoarseness and colds are 
common among smokers. 

The ''inhaling' 7 of cigarette or 
cigar smoke is especially harmful 
because it seriously hinders the 
work of the air cells in the ex- 
change of gases with the blood cells. 

Fig-. 85.— Showing- harm- t^ addition cigarette smoke is 
ful posture caused by Ln dauiLlun > cigdieue smoKC ±& 

high 15 at a desk t0 ° rea( iily absorbed by osmosis and 

the poison is taken at once to the 
tissue cells and impairs their usefulness. 

This is shown after a few years' use by "nervousness," 
a "tobacco heart," a cough, anemia and generally lowered 
vitality. 

Summary 

Dust from the streets, and other sources is ever present 
in the air. It is hindered from reaching the air-sacs of the 
lungs by the functions of the hairs of the nose, the mucous 
membranes of the nose and throat and the cilia of the air 
passages. 

Gases from the sewer, coal smoke and the manufacture 
of certain chemicals act as a poison when absorbed into 
the blood from the air when breathed. 



HYGIENE OF THE RESPIRATORY SYSTEM 193 

Exercise in the open air, as a daily habit, is conducive to 
good health and greater efficiency. 

Clothing worn too tightly interferes with proper respira- 
tion, as do wrong postures of the body when walking, 
sitting, or sleeping. 

Alcohol lowers vitality and increases the number of fatal- 
ities of pneumonia in chronic drinkers. 

It is not a preventive for colds and does not cure cough 
or la grippe. 

Tobacco is an irritant to the mucous membrane of the air 
passages, and its smoke, when inhaled, poisons the body 
cells and interferes with their wor_k. 

Questions 

1. What three provisions has nature made to free the 
dust from the air before reaching the air cells ? What are 
cilia ? What is their functions ? How do they operate ? 

2. Name several trades which produce dust? What 
protection should the workers employ ? 

3. What is the best way to " sweep " a room? What is 
the worst way to do it? What effect does oiled sawdust on 
a floor have when it is being swept? How should a room 
be dusted to avoid "raising" a dust? 

4. Why is street dust, especially in larger cities, 
dangerous ? 

5. Why is the inhalation of coal smoke injurious ? How 
can a city become i i smokeless ' ' ? 

6. What danger is there in working in match factories 
and some chemical works ? How can it be avoided ? 

7. What is sewer gas ? How may it reach the living or 
sleeping rooms? Why is it harmful when breathed for a 
number of days ? 



194 PHYSIOLOGY, HYGIENE AND SANITATION 

8. Name four effects of exercise? Why should exercise 
be taken in the open air ? What are good bedroom exer- 
cises ? When should they be taken ? 

9. What bad effects has the wearing of tight clothing? 
Why are tight corsets injurious? 

10. What is the effect on respiration of a stooped 
posture ? How should one walk with reference to a proper 
supply of air? Sit? Sleep? 

11. When an excess of alcohol is drunk how is some of it 
eliminated ? What happens to it in the tissues ? Why are 
habitual drinkers more liable to the disease of the respi- 
ratory organs? Is whiskey a good preventive of colds? 
La grippe and pneumonia? Why? 

12. What is the effect of tobacco on mucous membranes 
of the air passages ? Why is the inhaling of cigarette smoke 
especially harmful? What conditions finally develop as 
a result of continued and excessive use of cigarettes ? 



CHAPTER XXVI 

INFLUENZA AND "COLDS" 

Germs in the Air. The air under certain conditions 
may convey many forms of germ diseases from those 
who are sick to healthy persons and produce in them like 
diseases. Among these are "bad colds," influenza, pneu- 
monia, diphtheria, scarlet fever, and whooping cough. 

"Bad colds" are, perhaps, most frequently so carried. 
This disease is an inflammation of the mucous membrane 
of the nose, and is caused by the growth of germs. A 
person with a cold may sneeze and by doing so, if one 
has not learned to cover his nose and mouth with a hand- 
kerchief, the germs of his disease may be sprayed 
through the air several feet in the direction in which his 
nose is pointed. These germs may be at once inhaled 
by another person, and, if conditions are favorable for 
their growth, they will begin to multiply in the new nose 
and another "bad cold" is the result. The danger of 
colds is in the frequency of their bad ending — in bron- 
chitis, pneumonia, or inflammation in the ears. 

Influenza, sometimes called LaGrippe, Spanish Influ- 
enza, "The Flu," is a disease spread like "bad colds" 
almost entirely by careless coughing, spitting, sneezing 
and talking. At times it spreads with great rapidity, at 
which time it is said to be epidemic. 

This disease in the later months of 1918 killed more 
than 200,000 people in the United States, and many mil- 
lions were made ill. It began in Spain and followed the 
routes of travel, reaching New York first, and spreading 
rapidly over the Eastern, Southern, Northern, and West- 

195 



196 PHYSIOLOGY, HYGIENE AND SANITATION 



ern parts of the United States and into Canada and Mex- 
ico. Schools were closed. Doctors were not able to visit 
many who were seriously ill, and nurses were too few to 
wait on the sick. "Whole families often were in bed at one 
time. 

This is a typical germ or seed disease and the germs 
were carelessly coughed, sneezed, or spit about, so that 

well people who 
were unfortunate 
enough to come 
near such people 
or places, where 
they had been, 
were at once in- 
fected. 

If every person 
who was ill of in- 
fluenza had known 
what this book 
tea ches concern- 
ing the spread of 
diseases and their 
prevention, and 
had applied that knowledge, this disease would have been 
confined to the first cases. 

Influenza begins with aching pains in the muscles, some 
headache and fever, a mild cough and a feeling of weak- 
ness. 

In mild cases, recovery is rapid and free from after- 
effects except a feeling of continued weakness. Most 
cases are mild and for this reason it has been called 
"Three-day Flu." In the severe cases, pneumonia and 
pleurisy often develop with frequent deaths. On the 




Pig-. 



-The germs of influenza. 



INFLUENZA AND "COLDS" 197 

first appearance of the signs of the disease, the person 
should go to bed and send for a good physician. 

A person having ififluenza should not cough or sneeze 
except into a handkerchief, which should be kept moist 
with a five per cent, solution of carbolic acid. Bating 
utensils, as knives, plates, cups, forks, glasses, and spoons, 
after being used by the patient, should at once be well 
boiled. 

The victim should be placed and kept in a room alone, 
except for the one who is doing the nursing, until every 
sign of the disease has disappeared. Bed clothing used 
by the patient should not be used until it is sterilized 
either by boiling, the use of chemicals, or long exposure 
to sunlight. Visitors should be denied admittance. 

Prevention of Influenza. When an epidemic of the dis- 
ease appears, people should stay at home ; avoid crowds 
of people and crowded cars, churches, theaters, and other 
public meeting places. 

Fresh air in abundance in the living and sleeping rooms 
should be supplied. Exercise and regular hours for the 
body's habits and for eating and sleeping must be prac- 
ticed. 

Alcoholic liquors are useless as a preventive and may 
be harmful by lowering the resistance of the body to 
infection. 

Beware of the man who sneezes and coughs at you. 
His is a dangerous weapon and his charge spreads like 
a load of bird shot. About five feet is the limit of his 
range. 

If one develops the "Flu" no alarm should be felt for 
its death rate is lo^when compared to the entire number 
who are ill, and the death rate is probably higher among 



198 PHYSIOLOGY, HYGIENE AND SANITATION 

persons who foolishly allow themselves to become fright- 
ened. 

Upon the appearance of a slight cold, which may be the 
beginning of influenza, the nose should be cleansed with 
a warm solution of common salt in water — a teaspoonful 
to the pint of water. This may be done with a spray, 
or by holding a bit of the solution in the hollow of the 
hand and "sniffing" it up the nose repeatedly. At in- 
tervals of two or three hours it may be repeated. "Do- 
bell's Solution" can be used in the same way and may 
be purchased at any drug store. A hot bath at night and 
a warm bed with plenty of fresh air in the sleeping room 
are excellent aids in the prevention of this and like 
diseases. 

Every citizen should obey the rules and regulations 
of the health authorities for prevention of the disease and 
insist that others do so. 

Summary- 
Many diseases of the air passages result from the in- 
halation of the germs or seed which produce them. 

Infections of the nose are the commonest example of 
the spread of such diseases by careless spitting, cough- 
ing, sneezing, or talking. 

Influenza is a common infection in the United States, 
and ordinarily, is of a mild type. In epidemic form, its 
complications bring disaster. 

Influenza, in epidemic form, can only be controlled by 
the united effort of all the people who know how to pre- 
vent its spread and who help to do it. 

Crowded places, over-heated houses, poorly-ventilated 
sleeping rooms, poor food, intemperance, and irregular 



INFLUENZA AND " COLDS' ' 199 

hours are favorable for the spread of this and like dis- 
eases. 

Questions 

1. Name six diseases that may be spread at times by 
inhalation of germs in air? Why? 

2. What is a "bad cold"? What causes this disease? 
How would you protect other members of your family 
or school-mates from this disease, if you had it? 

3. What danger, if any, is there in "bad colds"? 

4. What other names are given to influenza? How is 
it spread? What is an epidemic of the "Flu"? What 
can you say of the epidemic of 1918 ? 

5. How does influenza affect one at the beginning? 
How long does a mild case usually keep one ill? 

6. What serious complications sometimes follow in an 
attack of influenza ? 

7. What is the first thing to do when this disease de- 
velops? What precaution should be taken by the patient 
when he sneezes or coughs? 

8. How much carbolic acid should be stirred into a 
quart of water to make a five per cent, solution? 

9. Why should a victim of influenza be kept isolated 
or alone? What should be done with a patient's cloth- 
ing and bed-covering before they are used by anyone 
else ? 

10. Why should crowds of people be avoided when an 
epidemic of influenza is present in a community? What 
is the most abundant, cheapest and one of the best pre- 
ventives of influenza? When and where should it be 
used? What body habits should be practiced as a safe- 
guard against the disease? 



200 PHYSIOLOGY, HYGIENE AND SANITATION 

11. Is alcohol, as in whiskey, beer, or wine, a preventive 
of la grippe ? Why ? 

12. Why and when is an unguarded sneeze or cough 
of a "Flu" victim dangerous? 

13. How may a "cold" or a beginning attack of in- 
fluenza be treated with benefit? What cleansing fluids 
may relieve such an attack? How should they be used? 

14. What is the value of hot baths and fresh air in 
sleeping rooms during an epidemic of influenza? 



CHAPTER XXVII 

TUBERCULOSIS 

Frequency of Tuberculosis. Tuberculosis or "consump- 
tion" kills about one of every seven people in the civilized 










fe'^ " 


~ *i Ellfc^.S 







Fig-. 87.— Showing- great destruction of lung tissue from 
tuberculosis. (A.) 

world. So destructive is it, that it is well called the ' ' Great 
White Plague." 

So general is it that it is presumed that nearly every- 
body, some time in life, has been infected with tuber- 
culosis, many getting well without ever knowing of their 
having it. 

In the dissecting rooms of medical colleges and large 

201 



202 PHYSIOLOGY, HYGIENE AND SANITATION 



hospitals, thousands of lungs have been carefully examined 
after death and infections of tuberculosis have been found 
in about eighty per cent, of all the lungs examined. Many 
of these people had died from other causes and most of the 
spots or areas of infection had been healed or made 
harmless. 

As only about fourteen per cent, die of this disease it is 
readily seen that the great majority of people recover from 
its attack. 

Site of the Disease. Tuber- 
culosis may attack the bones, 
brains, intestines, glands, lungs 
or any tissue of the body. The 
most frequent site of attack is 
in the lungs, where it is com- 
monly spoken of as "consump- 
tion," or "weak lungs." 

The Cause of Tuberculosis. 
Until 1880, the cause of tuber- 
culosis was unknown. Dr. 
Koch, in this year, showed that 
in every case of tuberculosis 
there was present a tiny rod- 
shaped seed or germ; that this germ, if introduced into a 
healthy animal, like a dog, cat or guinea pig, would repro- 
duce in a few weeks a like disease in such animals; and 
that this germ was never found in any other disease ex- 
cept tuberculosis. 

This germ is a bacillus in shape and is named the tubercle 
bacillus. It grows like other germs, in the presence of food, 
warmth, moisture and in the absence of sunlight. It is so 
email that many thousands of them grouped together, could 
not be seen with the naked eye yet they have been grown 




Fig-. 88.— Tubercle bacilli— 
the germs growing- in the 
walls of an air-sac. 



TUBERCULOSIS 



203 



in laboratories in such numbers that one lump of them 
weighed a pound. 

No one can develop "consumption" unless this germ or 
seed is planted in the body. 

Tuberculosis is the result of the growth in the body of 
germs or seed of the disease, just as a stalk of corn is the 
result of the growth of a grain of corn planted in the 
ground. 

Conditions must be favorable for the growth of the 
germs in the 
body, else they 
die, just as con- 
ditions of weath- 
e r, soil and 
moisture must 
be favorable for 
the growth of 
the seed of corn 
in the ground. 

If consump- 
t i on germs 
would grow and 
produce the dis- 
ease every time 
they get into the body, the human race would have died 
long ago. Such germs and many others are prevented 
from growth by the resistance of the body cells through 
immunity, and the action of the white blood cells which 
try to destroy them. 

The Signs or Symptoms of Tuberculosis. Tuberculosis 
should be recognized early in its course for it is in this 
stage that it is most easily cured. Its presence in the body 




Fig-. 



-A strong 
a full, 



healthy pair of lungs with 

devlecped chest. 



204 PHYSIOLOGY, HYGIENE AND SANITATION 



gives rise to certain signs or symptoms which will lead one 
to consult a competent physician. 

One of the early signs noticed is a loss of weight. In a 
period of several weeks, one may lose ten or twenty pounds 
for no apparent reason. The appetite is probably "fickle,' 
some days one is very hungry and, again, there is little or 
no appetite for food. 

A little fever appears nearly every day, especially, in 
the afternoons, and its presence 
will be shown by flushed cheeks or 
the "hectic flush." The use of a 
physician's thermometer each day 
will establish the fact of fever. 

A slight, hacking cough appears, 
which is most in evidence upon 
rising from sleep. After some ef- 
fort, a bit or "plug" of mucous 
may be coughed from the lungs. 
This should be collected in a clean, 
wide-mouth bottle and sent to a 
laboratory, where the microscope 
may reveal the presence of the 
seed or germ of the disease. 

If the germs are found, it is a 
final and positive proof that the one coughing up such 
material has tuberculosis. If the report states that the 
germs were not found, it is not final proof that one does not 
have the disease, because there may not have been any 
germs in that particular bit of mucous, and other specimens 
should be sent for examination. 

Examination by a Physician. A competent physician 
when asked to make an examination of tuberculosis, will 
not ask a few questions, "look at the tongue" and 




Fig*. 90.— A consumptive 
who has lost weight. 
Note the thin chest. 



TUBERCULOSIS 



205 



write an order for medicine, but will remove the clothing 
from the chest, and make a careful physical examination. 

A physical examination of the chest will show a differ- 
ence, if any, in the size of each side in inspiration; the 
presence or absence of any peculiar cracking or bubbling 
sounds in the air tubes ; the change in voice sounds, if the 
disease is pres- 
ent ; the pres- 
ence or absence 
of cavities or 
" spots" in the 
lung ; any 
change in the 
shape of either 
side of the 
chest ; shallow 
or deeper 
breathing o> n 
one side or the 
other, and many 
other points 
which t o the 
trained doctor 
may mean the 
presence or ab- 
sence of tuber- 
culosis. 

A physician will cause the "temperature" and weight 
of the body to be recorded daily for several weeks, and will 
make many inquiries to learn if one has been closely asso- 
ciated with a tuberculous victim or if the disease "runs in 
the family." 

Heredity of "Consumption." It was thought for a long 



ftll;,:: : 


iSlllIlli^^,:! 


1 






i 

plpilii 


flf 








[ PM'£&Si ; '~v. 


; *> 4" 






'•/ ; 










. '.''■'■'■ .: ■ ■ ■ 


^i:-^&P ' . 








■ ' ■ : ■ 














yaffil 




■; : |§ 


^i 





Fig-. 91.— A cavity in the upper lobe of the 
lung, caused by the growth of tubercle 
bacilli. (C.) 



206 PHYSIOLOGY, HYGIENE AND SANITATION 




Fig. 92.— Listening- for unusual 
breathing sounds— part of a physi- 
cal examination. 



time that tuberculosis was inherited from parents to chil- 
dren. It is now known that this is not true. 

Tubercular parents 
are usually not very 
"strong" and often 
have low vitality. Their 
children naturally are, 
as a rule, "weakly" and 
lack resisting power, 
and, for this reason, 
more likely to develop 
the disease, if the germs 
or seed find their way 
into their bodies. 
A new-born baby may have a mother, who has "advan- 
ced" tuberculosis, or be in the 
1 ' last stages ' ' of the disease, but 
the lungs x>r other tissues of the 
baby, when born, are always free 
from the germs of the disease. 
Unfortunately, most mothers do 
not know how to prevent the 
spread of this disease and the 
baby often becomes infected in 
the early days of its life. 

How the Disease Spreads. The 
germs of consumption are often 
destroyed by white blood cells 
in the lungs. The attacking germs 
attempt to grow in the warm, 
moist, dark lungs, which furnish 
them plenty of food. At once the alarm is given and na- 
ture sends out her army of "policemen," the white 




Fig. 93.— Feeling for un- 
usual vibrations from 
the victim's voice in a 
physical examination. 



TUBERCULOSIS 



207 



blood cells, and a great fight to the "last man" occurs. If 
the white blood cells are the victors (and they are in the 
great majority of "fights" or infections), the lung tissue 
becomes normal or well. 

Tf the germs are numerous, persistent and strong, the 
lung cells are "broken down" or destroyed, as the army of 
white blood cells is forced farther away from the scene of 
the first attack. 

These infected "spots" become large enough to be seen 
with the naked eye and the fight continues or stops depend- 
ing on the strength of 
the opposing sides. 

Often these spots, 
or infected areas, be- 
come as large as a 
marble, a plum, or an 
apple and the white 
blood cells succeed in 
limiting the spread of 
the destruction by 
building a wall or 
sac all around the in- 
vading germs and the 
tissue which has been destroyed. The disease then may be 
said to be " arrested ' ' and the signs of fever, loss of weight, 
cough, and fickle appetite will disappear. It is during this 
early, ' ' active ' ' stage of the disease that the patient has the 
best chances of. recovery with prompt treatment. 

It is in this stage, also, that nature assists the blood cells 
in the fight, by coughing. This effort is made to force the 
germs and destroyed tissue out of the bronchial tubes and 
air passages into the outside world. One bit of such ma- 
terial coughed up may contain millions of living seed of 




Fig-. 94.— A reclining- chair commonly 
used by consumptives for rest and 
comfort. 



208 PHYSIOLOGY, HYGIENE AND SANITATION 



the disease. If these are not destroyed, they may grow in 
some one else's body. 

If every consumptive would now begin to destroy the 

seed of his disease as soon as they come from the body, 

tuberculosis would disappear from the world as soon as 

all who now have it recover or die. 

A consumptive person, who is ignorant or careless, may 

infect all of his fam- 
ily and many other 
people. His lungs 
may be said to be a 
"store-house" of liv- 
ing seed, and his nose 
and mouth usually 
contain the germs of 
tuberculosis. 

In talking or sneez- 
ing or coughing, the 
droplets of saliva 
may carry these seed 
into the mouth or 
nose of some one 
near. The "sputum" 
or matter coughed 
from the lungs, if 
1 c spit ' ' or expecto- 
rated on the floor, or side walk or about public places, is 
dangerous for many reasons. 

Such sputum may become half-dried and the dust from 
sweeping the floor will float living germs through the air 
passages into the air sacs of the lungs, or the tonsils may 
fail to filter them out, and the germs may find their way 




Fig-. 95.— A simple and inexpensive sleep- 
ing- porch. 



TUBERCULOSIS 



209 




Fig-. 96.— A "hollow chest" 
in advanced tuberculosis. 



through the lymphatics into the lungs, or bones or other 
tissues of the body. 

When tuberculosis attacks the 
lymphatic glands in the neck 
they become large and often 
"run" or discharge " matter" 
or pus. This condition is com- 
monly called "scrofula." 

Plies readily eat sputum and 
often get their feet loaded with 
tubercle bacilli. Their next visit 
may be to some article of food, 
such as a glass of milk in which 
they may "take a swim." The 
living seed of the disease are 

thus washed off in the milk. Milk infected in this and other 
ways have been the means of 
infecting hundreds of thous- 
ands of people. 

Infected sputum on the 
side walks, floors and in pub- 
lic places, may be carried by 
rats, or on the feet into the 
house where in some way it 
reaches the food or is 
breathed with dust into the 
lungs. 

The germs of tuberculosis, 
like most other germs that 
produce disease, are easily 
killed by strong sunlight. 
Thorough drying also destroys them. In half-dried 
sputum which may become broken up and be mixed with 
dust, they may live for weeks. 




Fig*. 97.— A bed in a screen- 
ed porch protected from 
wind and rain by curtains. 



210 PHYSIOLOGY, HYGIENE AND SANITATION 

Bed-clothing used by a consumptive may remain danger- 
ous for this reason for months. Such clothing should never 
be used after being purchased at second-hand stores or 
public sales until it has been boiled or "sunned" for many 
days. 

Untidy, tuberculous waiters, cooks, clerks in food stores 
and laundry-women often carry infected sputum into the 
home where, through the food or air, the disease seed may 
be planted in the body. 

Milk cows, on the farm, or in a dairy, many times are 
victims of tuberculosis in such a form that the seed of the 
disease escape in the milk. Babies often, after using such 
milk, develop tuberculosis of the bowels, which in later life, 
is carried by the blood or lymph to the lungs, where ' c con- 
sumption ' ' develops. 

Milk cows should be tested for tuberculosis and if in- 
fected, should be killed. 

Summary- 
Tuberculosis is a world-wide disease, which attacks, 
probably, nearly every one sometimes during his life. Most 
people recover. It kills about one of every seven people of 
the civilized world. Its usual site of attack is the lungs. 

The tubercle bacillus is its seed and, under favorable 
conditions, will grow in the body, or in special foods pre- 
pared in laboratories. 

The leading signs of the disease are loss of weight, fever, 
cough and disturbances of appetite. The discovery of the 
germs in sputum is final proof of tuberculosis. 

It is not inherited but "runs in families" because the 
germs are present and "sown" among other members of the 
familv. 



TUBERCULOSIS 211 

The germs are spread by the unguarded coughing, sneez- 
ing, talking or spitting of one who has the disease in an 
active stage. 

They may be inhaled or swallowed with dust, food or 
drink. 

Questions 

1. What are two other names for tuberculosis? 

2. How many people of the civilized world of every 
hundred are presumed to have had it, some time in their 
lives ? How many of such people die of it? About what 
per cent., therefore, recover or die of some other cause? 

3. What tissues may tuberculosis affect? Where is its 
usual location ? What grows tuberculosis ? When was this 
fact discovered ? How did Dr. Koch prove this fact ? 

4. What are the conditions necessary for the growth oi 
the germ of consumption ? Why do they ever grow in the 
human body ? 

5. What would happen if the germ of tuberculosis should 
grow in the body, undisturbed, every time they should enter 
it? What prevents their growth, most of the time, in the 
body? 

6. Name four symptoms or "danger signs' ' of tuber- 
culosis. 

7. What is meant by a "fickle" appetite? 
S. What is meant by a " hectic flush ' ' ? 

9. What is the final proof of existence of tuberculosis in 
the body? 

10. What is a "physical examination"? When and by 
whom should it be made ? 

11. If you should ask a physician to examine you for 
tuberculosis and he should ask a few questions, feel your 



212 PHYSIOLOGY, HYGIENE AND SANITATION 

pulse, look at the tongue and give you some medicine, would 
you consider him a competent doctor? "Why? 

12. Name four conditions which may be shown by a 
physical examination? 

13. Is consumption "inherited"? Explain why several 
people in the same family, often, have tuberculosis ? 

14. "Why may the lungs be a good growing place for the 
seed of tuberculosis? What is the greatest enemy to the 
growth of germs in the lungs ? 

15. After a lung is infected, explain how it may get 
well? When is a part of the lungs said to be "broken 
down" or destroyed? 

16. If tuberculosis has destroyed a part of the lung as 
large as an apple, may the patient get well ? Explain how 
this happens? How may it be known that the disease has 
been arrested? 

17. When is tuberculosis most easily cured? 

18. Why does a person, who has this disease, cough? 

19. How do tubercle bacilli escape from the body in 
tuberculosis of the lungs ? 

20. How and when might tuberculosis disappear from the 
earth? (See paragraph in black type). 

21. How may a consumptive infect his friends and fam- 
ily? What is sputum? What is expectorated sputum? 
When is it dangerous? How may it be inhaled into the 
lungs? 

22. Show how flies may spread consumption ? 

23. What is "scrofula"? 

24. How may infected sputum of the sidewalks or on the 
floors be mixed with our food ? 

25. What is the effect of sunlight and drying on these 
germs ? 



TUBERCULOSIS 213 

26. When may used bed-clothing be dangerous? Why? 
How should it be treated before being used ? 

27. How may milk sometimes carry tubercle bacilli into 
the body? What part of the body is often thus first 
infected? 



CHAPTER XXVIII 



TUBERCULOSIS (Continued) 




Fig". 98.— A paper lining 
which can be lifted from 
the cup and burned. 



Prevention of Tuberculosis. The best preventive of 
this and most other diseases is to keep the body healthy 

and strong by proper exercise, 
good food eaten at regular hours, 
plenty of fresh air, day and 
night, sufficient work to keep 
one busy, regular hours for sleep 
and rest and avoidance of vicious 
habits, including the use of to- 
bacco and alcohol. 

One may live, with safety, in 
the same house with a consump- 
tive, if certain precautions are 
being taken by the victim and the nurses. 

Care should be used to collect and destroy sputum. This 
can be done by spitting it into sputum cups. These are 
usually made of tin with a spring top, 
with removable paper linings. The in- 
side may be lifted out and burned. 

When the patient coughs or sneezes, 
the mouth and nose should be covered 
with a soft cloth which may be carried 
in paper-lined pockets or kept moist 
with a five per cent, carbolic acid solu- 
tion. 

The hands should be frequently wash- 
ed. Eating and drinking utensils 
after being used by the patient, should be at once 
boiled. 




Fig-. 99.— A t i n 
sputum cup with 
a spring top. 



214 



TUBERCULOSIS 



215 



The patient should sleep alone in a well-ventilated, 
screened room or in a screened sleeping porch. No rugs 
or carpets should be on the floors, and the bed clothing 




Fig. 



100.— An ordinary tent with a wooden floor for 
out-door treatment. 



must not be used by others unless it has been thoroughly 
boiled or sterilized. 

Floors should not be swept with a dry broom, but 
should be rubbed with an oiled or wet mop. 

The hands of the attendant should be washed before 
each meal. 

The patient should not swallow sputum, because its 
germs may grow in the bowels; the mouth and teeth 
should be washed often to avoid this danger. 

The patient should spend a few months in a tubercu- 
losis sanatorium until recovery results, or until one may 
learn to live in safety with his family and friends. 

Treatment of Tuberculosis. Rest, sunlight, fresh air, 
good food, and a good doctor are the five needs for cur- 
ing tuberculosis. 



216 PHYSIOLOGY, HYGIENE AND SANITATION 

Rest in bed should be the rule as long as there is fever. 
Exercise is often hurtful and should not be done only 
when ordered by the physician. 

Milk, meat and eggs are three good foods and their 
quantity should be regulated by the doctor. 

Consumptives should cough only as often as is needed 
to empty the air passages of mucous. Hard efforts in 




Fig-. 101— Out-door treatment of tuberculosis. 

coughing may burst a blood vessel in the lungs, causing 
a "hemorrhage" of the lungs, and may cause the infec- 
tion in the lung to spread. 

Consumptives should sleep in the open air, winter and 
summer. Protection from drafts of cold wind may be 
had by the use of awnings or sheets; the body may be 
kept warm in very cold weather by woolen blankets, 
woolen helmets and hot water jugs. 

Window tents may be used instead of sleeping in sleep- 
ing porches. These are usually made of canvas and are 
so arranged that a patient may remain in his warm room 
and have his head at an open window through which he 



TUBERCULOSIS 



217 



may get plenty of fresh air and be protected from rain, 
snow, and drafts. 

A woolen helmet in cold weather protects the head 
and ears. 

Medicines are of little value in curing tuberculosis and 
should only be given by the doctor. 

Patent medicines are usually harmful because they 
may contain alcohol or other habit-producing drugs and 




Fie 



102.— An out-door school for children who are in 
danger of developing- tuberculosis. 



cause a patient to rely on drugs rather than the out-door 
rest treatment. 

Summary 



A healthy body is the best protection against tuber- 
culosis and most of the other diseases. 

With certain precautions observed by the victim of 



218 PHYSIOLOGY, HYGIENE AND SANITATION 

tuberculosis and the attendants, one may live in safety 
in the same house with a consumptive. 

The prompt collection and destruction of sputum is a 
simple rule for the prevention of the spread of the 
disease. 

A course of treatment in a tuberculosis sanatorium 
will teach a person how to live with safety to others at 
home. 

The treatment of tuberculosis should be in the hands 
of a competent doctor and consists of rest, food, sunshine, 
and fresh air. Medicines are of little value and "patent 
medicines" are often harmful. 

Questions 

1. What is the best preventive for tuberculosis? 

2. "What are the six general rules of health for keeping 
the body well and strong? 

3. May a person live in safety in the same house with 
a consumptive? Under what conditions? 

4. What should be done with the sputum? How is it 
done ? 

5. What precaution should be taken when coughing or 
sneezing ? 

6. Why should the hands of the patient and the at- 
tendants be frequently washed? 

7. Why should the patient sleep alone? Where? Why 
use screening? What is the danger in the bed clothing 
of the patient if used oy others, without it is sterilized ? 

8. How should the floors of such a bedroom be cleaned? 

9. Why should not a consumptive swallow his own 
sputum? Why should his teeth and mouth be washed 
frequently ? 



TUBERCULOSIS 219 

10. What are the advantages of a period of treatment 
in a tuberculosis sanatorium? 

11. What five great means are there for the cure of 
tuberculosis? 

12. What is the value of rest in the treatment? 

13. Why may exercise be harmful during the fever 
stage ? 

14. Name three good foods for consumptives. How 
should they be given? 

15. What bad effects may there be from coughing too 
much or too hard? 

16. Where should consumptives sleep ? How may they 
be protected in cold weather? 

17. What is the use of window tents? How are they 
used ? 

18. What is the value of medicine in the treatment 
of this disease? Why may "patent medicines' ' be 
harmful ? 



CHAPTER XXIX 

THE EXCRETORY SYSTEM 

We have learned in preceding chapters that the body 
is a great " workshop " or laboratory, where foods, air, 
and water are prepared and used to make heat, energy, 
and flesh, blood, and bones. 

The work of the body is done by the systems of the 
body working in harmony and helping each other. 

"When work is done in any factory, kitchen,, shop, or 
laboratory, there is always a lot of waste material or 
" scrap" made which must be cleared out of the way in 
order that work may not be delayed or impaired. 

The human machine is the most wonderful and complex 
workshop in the world. It performs thousands of duties 
every hour and its operations involve most delicate and 
scientific work. 

There are poisonous gases made, which must be thrown 
out of the body. Much of the food we eat is of no value 
and it must be cleared out of the way. Broken-down 
body cells would clog the machinery, if they were not 
removed. Sickness produces many poisons in the body. 

The work of ridding the body of its wastes is done by 
the excretory system and much of it is done by organs 
which assist in the work of other systems. 

The Organs of the Excretory System. Body wastes are 
removed mainly by the action of the kidneys and bowels, 
and they are aided by the action of the lungs and skin. 

The Kidneys. The kidneys are located deep in the 
back just in front of the spinal column. They are two 
in number, dark red in color, and shaped like a dried 

220 



THE EXCRETORY SYSTEM 



221 



bean. They are usually surrounded by fat and weigh 
about four ounces each. They are plentifully supplied 
with blood and as it circulates through them, the poison, 
collected from body cells, is filtered out. 




Fig-. 103.— Showing relations of kidneys, blood vessels 
and bladder. 



The chief poisons excreted or thrown out by the kid- 
neys are those from proteids from the body cells or im- 
perfectly assimilated foods. 



222 PHYSIOLOGY, HYGIENE AND SANITATION 

The blood, at the same time, of course, is circulating 
through the lungs and carbon dioxide, from the oxida- 
tion (burning) of food in the tissue cells, is thrown out 
of the body in the expiration of air from the lungs. 

The wastes from the kidneys, which are dissolved in 
water trickle through two small tubes, to a reservoir — 
the bladder — in the lower part of the abdomen. 





Fig-. 104.— The right kidney. Fig-. 105.— The left kidney. 

A. Artery. V. Vein. U. Tube leading- to the bladder. 

Hygiene. Water is the fluid which nature uses so freely 
in performing all of her operations in the body. 

Food is reduced to a fluid with it ; the blood flows like 
water; the sweat or perspiration is mostly water; the 
kidneys remove body wastes in water; the bowels require 
much water to throw off refuse matter ; the lungs throw 
out water with each breath and more than three-fourths 
of the total weight of the body is water. 

It is quite evident that water should be drunk freely, 
if poisons are to be thrown off and the work of the body 
is not to be hindered. 



THE EXCRETORY SYSTEM 223 

Water should be drunk freely throughout the day. A 
glass or two after rising and washing the teeth, should 
be drunk before breakfast ; three or four glasses during 
the morning, and as many more during the afternoon 
should be drunk, and, at least, two before retiring. 

A half-gallon of water a day is the least amount an 
adult living a sedentary life should use. Persons doing 
hard labor frequently drink a gallon or more a day, much 
of it escaping from the body as "sweat." 

Too much water should not be used with the meals, 
but a glass or two is not believed to do any harm, and 
it is now believed by many authorities that it aids nature 
in preparing the food for absorption. 

Alcohol is, especially, harmful to the kidneys because 
its habitual use impairs the work and structure of body 
cells, and more poisons are thrown into the blood for 
the kidneys to remove. This overworks the kidney cells 
and they often "break down" and escape with the body 
wastes. 

Blight's Disease is common, after continued use of al- 
cohol, and the working cells of the kidneys are slowly 
destroyed until the accumulation of body wastes, which 
cannot be removed, poisons the victim. Alcohol often 
causes a growth of fat inside the kidneys and their work 
is impaired and the body suffers. 

The Bowels. Every modern city or factory provides 
a way to rid itself of waste matter. The fluid wastes of 
a city are usually carried away by a sewerage system 
which consists of a large outlet pipe into which run the 
hundreds of smaller pipes from homes, factories, and 
office buildings. 

Were this provision not made, the city would be filled 
with foul odors and decaying matter, which would soon 
cause diseases and ill health. 



224 PHYSIOLOGY, HYGIENE AND SANITATION 

The bowels are the great sewer of the body, which 
assist it in removing its body wastes. 

It is important that plenty of water be used to assist 
nature to clear away the waste materials from the body. 

Regular habits should be practiced for, if body wastes 
are not promptly removed, the poisons from the bowels 
are absorbed into the blood and body cells are impaired. 
Headaches may occur, and anemia and general ill health 
may result. 

Fruits, as apples, figs, and prunes, aid the bowels to 
remove wastes from the body, and may be eaten with 
the meal or at bedtime. 

Such body wastes, during the course of typhoid fever, 
dysentery, "summer complaint" of children, cholera, and 
hookworm disease contain the seed of these diseases, 
and if they are not properly handled and destroyed, 
these seed may become scattered and grow in another 
person, causing a like disease. 

Medicines used instead of regular habits and use of 
fruits, food, plenty of water are to be avoided, as the 
habit of taking laxatives and purgatives is soon formed, 
hard to break, and harmful. 

Summary 

The excretory system removes waste materials from 
the body, through the action of the kidneys and bowels, 
aided by the lungs and skin. 

The kidneys filter the poisons of the body cells (main- 
ly) from the blood. Plenty of water should be drunk 
to help them do their work. 

Alcohol is destructive to kidney cells, when it is used 
excessively or continuously, and often causes Bright 's 
disease. 



THE EXCKETORY SYSTEM 225 

The bowels assist nature in removing wastes from the 
body. During certain diseases these wastes, if not prop- 
erly disposed of, are dangerous for they contain the 
seed of such diseases as typhoid fever, dysentery, cholera, 
hookworm disease, and "summer complaint" of children. 

If these seed escape and find their way into another 
person, a like disease may be produced. 

Questions 

1. Explain why the body may be likened unto a "work- 
shop." What are "manufactured" in the body? Name 
four kinds of "wastes" which must be removed from the 
body. 

2. Why is an excretory system necessary? 

3. Name the two chief and two assistant organs of 
the excretory system. 

4. Describe the kidneys. What is their number, color, 
and shape? 

5. How do they remove poisons from the body cells? 

6. What rids the blood of carbon dioxide? How? 

7. Explain the uses of water in the body. 

8. When and how much water should be drunk daily? 

9. What is the effect of the continued use of alcohol 
on the kidneys? 

10. What is the effect of " Bright 's disease"? 

11. What is the function of a city sewerage system? 
Why is one necessary? 

12. What organ acts as a sewer to discharge certain 
body wastes? 

13. What bad effects on the body often result if such 
body wastes are not regularly removed? 

14. Name four things that may be used to assist na- 
ture to remove the wastes from the body. 



Phv.— 8 



CHAPTER XXX 

THE BODY WASTES IN DISEASE 

Typhoid Fever is a common and dangerous disease. 
It runs a course of four to eight weeks and leaves a vic- 
tim pale, greatly reduced in weight, weak and thin. Dur- 
ing an attack, the fever is high, the appetite poor, and 
often the patient is unconscious or delirious or "out of 
his head." About one in ten people who have the dis- 
ease die, and most of the "cases" occur in young adult 
life. 

It is a germ disease, and it can only occur in a person 

who in some way has 
swallowed the seed of 
the disease. It is not 
air-borne or carried to 
the body in any other 
way. 

The germs after be- 
ing swallowed attack 
the body through the 
mucous membrane of 
the small bowel, producing open sores or ulcers. Their 
growth there causes a poison which is absorved into the 
blood and produces the fever. 

The germs of the disease escape by the millions with 
the body wastes from the bowels and kidneys. 

It used to be common for typhoid fever to "go 
through" the entire family or neighborhood. Since the 
cause of its spread is known, a second case should not 
occur from the first one, when the disease appears. 

226 




Fig-. 106.— Ulcers in the small bowel 
caused by the growth of the germs 
of typhoid fever. 



THE BODY WASTES IN DISEASE 



227 



If the body wastes from every person who now has 
typhoid fever germs in the bowels could be properly 
handled and at once destroyed, there woxdd never be an- 
other case of typhoid fever in the world. 

How the Disease is Spread. The poisonous body wastes 
of a victim of typhoid fever are carelessly handled, and 
in many ways they may be carried into the stomach. 

The common house fly is a filthy and dangerous ani- 
mal because it has so often carried the seed of typhoid 
fever on its body to food. 
It has been well named the 
"typhoid fly." 

The body wastes may be 
ignorantly thrown on the 
ground, where they may 
wash or drain into wells, 
springs, cisterns, creeks and 
rivers. Such water, if used 
for drinking purposes, may 
carry into the bowels the 
living seed of the disease, 
and produce another case of 
typhoid. Numbers of cities 

have had "explosive outbreaks" of typhoid fever be- 
cause the infected water supply caused many cases of 
the sickness at or near the same time. 

The nurse or attendant may prepare food for the fam- 
ily without first thoroughly washing the hands and in- 
fected material may be swallowed with the food. 

Eats, mice, and dogs may soil their feet and carry in- 
fectious matter from foul places into the home, where 
in some way it reaches the food. 

A dairyman or his milkers may have typhoid fever in 




Fig-. 107.— The germs of typhoid 
fever. They have the power 
of movement in fluids. 



228 PHYSIOLOGY, HYGIENE AND SANITATION 




Fig-. 108.— The "typhoid fly.' 



the family and neglect to follow the rules for obtaining 
a clean milk supply and infectious material find its way 
into the milk. A great many cases of typhoid fever in 
cities have been found only in the customers of one 
dairy. 

Unsewered cities, as a rule, have a much higher sick 
and death rate from typhoid fever because there are 

more chances for infected body 
wastes to pollute the water or 
food. 

The Prevention of Typhoid 
Fever. Until every city, office, 
or public building and home are 
provided with a safe method 
of disposing of body wastes, 
every person is in danger of 
becoming infected with typhoid fever. 

The only safe method now known to prevent this dis- 
ease is by being "immunized" against it. A typhoid "vac- 
cination," in nearly every instance, prevents the disease 

for three or four years, when 
it may be repeated. (See 
page 153.) 

Body wastes from a typhoid 
fever victim should be at once 
placed in a solusion of fresh 
chloride of lime and allowed 

to remain three hours. Four ounces to a gallon of water 

make a solution strong enough to kill the germs. 

The hands of the attendant should be frequently 

washed. 

The sick room should be screened from flies, and every 

fly in the room killed. 




Figr. 109.— The eg-g-s of the 
house fly. 



THE BODY WASTES IN DISEASE 



229 



The changed bed-clothing should be soaked in a so- 
lution of chloride of lime before being removed from 
the room. 

No infected matter should be thrown upon the ground ; 




Fig-. 110.— Ninety per cent of house-flies are born 
in stable refuse. 



this includes water used for the bath of the patient 
The sewer or a ditch dug away from the water sup- 
ply may be used. If such material 
is thrown into a ditch it should be cov- 
ered at once with fresh lime and earth. 

If the drinking water is under sus- 
picion of being infected, it should 
be examined in a laboratory, and in 
the meantime all the drinking water, 
and that used for washing food eaten 
raw, should be boiled before using. 

If typhoid appears in a home or community, every person 
should be vaccinated for typhoid at once. 




Fig. 111. — The 
house fly seen 
from above. 



230 PHYSIOLOGY, HYGIENE AND SANITATION 

Summary 

Typhoid fever is a germ disease, and, therefore, a pre- 
ventable disease, and is caused by the growth of the 
germ in the bowels. 

Its seed escape wi£h the body wastes, and it can be pre- 
vented by properly disposing of such wastes. 

Flies, fingers, and food (including water) are the three 
principal means by which the disease is spread. 

Dairy milk may be infected with typhoid fever germs, 
if the disease is present in the family of the dairyman or 
his helpers and rules for supplying clean milk are not 
followed. 

Vaccination is the best method now known to prevent 
typhoid fever. Universal use of proper means of dis- 
posing of body wastes will abolish the disease. 

Care used in handling a typhoid fever patient will pre- 
vent the spread of disease. 

Drinking water, pending a laboratory report, should 
be boiled before used for drinking or washing foods 
eaten raw, as lettuce, tomatoes, apples, and berries. 

Questions 

1. What is the duration of an attack of typhoid fever? 
What effect does it have on its victim? What is the aver- 
age death rate of those who are ill of it? 

2. What is the cause of typhoid fever? How only can 
typhoid fever develop in a person? Can it be "breathed" 
into the body? Can it be "caught" through the skin? 

3. Where do typhoid fever germs grow? What causes 
the fever? 



THE BODY WASTES IN DISEASE 231 

4. What organs rid the body of the seed of typhoid 
fever ? 

5. How might typhoid fever disappear from the world ? 
(See black type.) 

6. Why is the "typhoid fly" a dangerous animal? 

7. How may the body wastes of a typhoid fever patient 
pollute drinking water? Should such water be used? 
Why? 

8. What is meant by "explosive outbreaks' ' of typhoid 
fever in cities? What is the cause of such an outbreak? 

9. What animals may infect food supply? 

10. How may typhoid fever in the family or helpers 
of a dairyman be carried to other people? Why? 

11. Why should cities be sewered? 

12. What is a simple and harmless method of prevent- 
ing typhoid fever? How long will this immunity last? 
Give six rules for preventing typhoid fever from ' ' spread- 
ing' ' when it occurs in the home. 



CHAPTER XXXI 



BODY WASTES (Continued) 




Hookworm Disease. In the warmer parts of the United 
States and in nearly all similar and torrid zones of the 
earth, hookworm disease is found. 

It does not often make one sick enough "to go to bed." 
It occurs most frequently in chil- 
dren who, unless treated, may 
carry the infection for many years. 
Victims of the disease are us- 
ually pale, undersized and weak. 
Their vitality is low and their use- 
fulness, therefore, is impaired. The 
disease when generally present, 
causes a great loss in money and 
efficiency to the community and 
the state. 

Cause of Hookworm Disease. 
The disease is caused by the pres- 
ence in the bowel of a tiny worm about an inch long and as 
thin as a thread. It is white in color and lives on the 
blood which it sucks from the tiny blood vessels of the 
mucous membrane of the bowel. 

Its head is furnished with tiny "hooks" with which it 
"holds on" and sucks the blood. One worm is said to use 
about a drop of blood every day. The body wastes of 
the hookworm are squirted into the blood of the victim 
which poison the blood and tissue cells. The loss of blood 
and the absorption of these wastes are the cause of the 
undersize and anemia of the victims when a large number 
of worms are present in the bowel. 

232 



Fig. H2.— T he mouth 
showing- the "hooks" 
of a full grown hook- 
worm. 



THE BODY WASTES IN DISEASE 



233 



J0 


^"Hfe 1 ^SsilS talk 


WmP% 


^3^^^ x\.. ' //;' ;. /•%:'*& 







These worms do not multiply in the bowel, but like most 
other worms they lay their eggs ; the female, at times, lay- 
ing as many as 
three hundred in a 
day, each of which 
is so small it can 
not be seen with 
the naked eye. 
These eggs escape 
from the bowel 
with other body 
wastes. 

If this material 
is carelessly dis- 
posed of and it 
reaches soft, moist, 
warm soil, the eggs 
soon "hatch, out" 
and in a few days they are in the infective stage. 

How the Worms Get Into the Bowel. These tiny worms, 
only a few days old, live in moist soil. If such soil is 
"worked" by the bare 
hands, or is walked upon 
by bare feet, these 
worms pierce the skin 
and get into the blood 
stream. They float 
through the blood ves- 
sels and when they reach the lungs, they break through the 
delicate lining of the air sacs into the bronchial tubes. 
When one coughs, these worms are "coughed up" and often 
swallowed, where they quickly reach their future home in 
the bowel and grow to their full size. 



Fig-. 113.— Showing- the hookworm feeding 
and attached to the wall of the bowel. 




Fig 



114.— The newly hatched 
worm (greatly magnified.) 



hook- 



234 PHYSIOLOGY, HYGIENE AND SANITATION 




A B 

Fig-. 115.— Eggs of the hook- 
worm. A. Beginning de- 
velopment. B. Ready to 
"hatch." (Magnified.) 



When these worms first enter the skin, they make a kind 
of "sore" called "dew-itch" or "toe-itch" or "dew- 
poison." The skin just under 
the bend of the toes is thin and 
this is the most frequent point 
of entrance. 

The Cure of Hookworm Dis- 
ease is very simple. The first 
step is to prove that the worms 
are present in the bowel. This 
is easily done with the aid of a 
microscope in a laboratory for 
the tiny eggs may be seen in such body wastes. 

The second step is to take a few doses of medicine under 

the care of a physi- 
cian. This will make 
the worms loosen their 
hold and they are 
made to escape with 
the body wastes. 

Hookworm disease 
untreated may last 
for years. Properly 
treated, it can be re- 
lieved, usually, in a 
few days.. 

Benefits of Treat- 
ment. The changes 
for good after such 
treatment are often 
truly wonderful. Chil- 
dren take on rapid flesh and growth ; their minds and 
bodies become active ; their color becomes ruddy and good 
health is enjoyed. 




A B 

Fig. 116.— A. Showing the boy before 
treatment for hookworm disease. B. 
The same boy a few months later. 



THE BODY WASTES IN DISEASE 



235 



Adults who, many times, were leading useless, workless 
lives are given new life and often become self-supporting 
and useful citizens. 

Prevention of Hookworm Disease. Proper disposal of 
the body's wastes will prevent hookworm disease and also 
typhoid fever 
and like dis- 
eases. 

Unfort- 
unately a 
great many 
homes, school 
houses, 
hotels and 
other public 
places have 
no proper 
place or 
method o f 
disposing of 
body waistes. 
A water- 
tight and fly-tight vault should be constructed at every 
such place and their use and care enforced by law. 




A B 

Fig-. 117.— A. Showing- the girl with hookworm dis- 
ease. B. .The same girl a few months after 
treatment. 



Summary 



Hookworm disease is prevalent in warm countries, long- 
continued in its effect, preventable and easily curable. 

It is caused by a parasite living in the bowels, which 
sucks blood and injects its own poison into the blood of its 
victim. 

Its eggs, under favorable conditions hatch and the tiny 



236 PHYSIOLOGY, HYGIENE AND SANITATION 

worms find their way through the skin of a victim into the 
blood stream, and through the air passages into the mouth 
where they are swallowed and carried into the bowels. 

The cure of hookworm disease consists in the removal by 
drugs of the worms from the bowel. 

Hookworm disease can be prevented by the proper dis- 
posal of the body wastes, by the use of sanitary closets. 

Questions 

1. Where is hookworm disease most often found? How 
long may an attack last ? 

2. Name five symptoms of hookworm disease. 

3. What is the cause of the disease? Describe a hook- 
worm ? What is its food ? How much food does it require ? 
How does it poison the body cells? 

4. What causes the anemia and reduced size of children 
who have severe hookworm disease ? 

5. How do hookworms reproduce themselves ? Where do 
they "hatch" best? 

6. How do young hookworms get into the skin? Into the 
lungs ? Into the mouth ? Into the bowels ? 

7. What is " toe-itch 7 '? Dew-poison? Dew-itch? If a 
bit of such skin were shaved off and put under a misroscope, 
what would you expect to see ? 

8. How is hookworm disease cured ? 

9. What effect will the proper disposal by everybody of 
the body wastes have on hookworm disease? 



CHAPTER XXXII 



THE SKIN 



The skin is the smooth, tough, and pliable covering for 
the entire body. At the ends of the fingers and toes it is 
changed in its structure to form the nails. Hair is a simi- 
lar modification of skin. 

At the entrances into the body the 
skin changes its structure and joins 
a more delicate and thinner lining, 
the mucous membrane. 

Functions of the Skin. Aside from 
its use in giving a finish and beauty 
to the body, it has four distinct func- 
tions. First, it forms a protective 
coating for the delicate blood vessels, 
glands and nerves; second, it is the 
seat of feeling by which we are made 
aware of pain, heat, weight, and cold ; 
third, it aids in regulating the heat 
of the body, and, fourth, it aids the 
lungs, bowels, and kidneys in remov- 
ing wastes from the body. 

Structure of the skin. The skin is composed of two 
layers ; the outer, horny layer, the epidermis and the inner, 
delicate one, the dermis or true skin. The epidermis has no 
sensitive nerves or blood vessels and is thick enough to pro- 
tect the delicate layer beneath. Who has not burned a 
blister on the hand? The elevated layer which fills with 
" water" (serum) is the epidermis. A needle may be 

23i 




Fig-. 118.— Stucture of 
skin. A. Epidermis. 
B. Dermis. (Great- 
ly magnified.) 



238 PHYSIOLOGY, HYGIENE AND SANITATION 



pushed through this layer without pain, but if the delicate 
dermis below is touched, pain is at once felt. 

" Corns" are thickened spots of epidermis and are caused 
by rubbing or friction. Shoes that are too loose, ill-fitting, 
or too tight often produce corns. The " horny' ' hands of 
a working man are made so by constant friction of tools in 
the hands. 

The epidermis is constantly be- 
ing worn away, and is as rapidly 
restored, by the growth of cells in 
the dermis. 

Complexions of the skin are due 
to the amount of coloring matter 
found in the epidermis. The color 
of different races of people is de- 
termined by the kind and amount 
of this coloring matter. The negro 
is dark or black for this reason. 

The dermis is plentifully sup- 
plied with nerves and blood vessels 
which end in tiny projections 
called papillae. 

The epidermis fits and is closely 
moulded upon these ridges. The 
nerve papillae are most numerous over the parts of the 
body with which one feels, as in the ends of the fingers, 
on the cheek, lips, and tip of the tongue. 

The lower layer of the skin is made up mostly of fat and 
connective tissue. These tw r o tissues make the skin 
tough, soft, and elastic or pliable, and form the bed for 
the hairs, sebaceous and sweat glands. 




Fig-. 119.— Finger prints 
of the epidermis. They 
are used to identify 
persons and are more 
constant and reliable 
than photographs of 
the face. 



THE SKIN 



239 




Fig-. 120.— Showing- A. Papillae with 
blood vessels and nerve ending's. 



Hairs are placed on the body for its protection. They 
are not found in the palms of the hands or soles 
of the feet. The hair of 
the head adds beauty to 
the body and protects 
the head against heavy 
blows. The hair of the 
nose and eyes help to 
protect the delicate 
membranes from dust 
and foreign bodies. 

The sebaceous glands 
in the deeper layer of 
the skin secrete and 

pour out an odorless oil which keeps the skin smooth and 
pliable. This is the oil which makes the hair smooth and 
glossy. 

The Sweat Glands are located in the deeper layer of 
the skin. Their mouths may be seen in the palm of the 
hands with a magnifying glass of low power. The blood 
capillaries carry certain body wastes to these millions of 
tiny glands over the entire body and they pour out a fluid, 
the sweat or perspiration, which contains waste materials 
from the cells. By this action, the heat of the body is 
regulated. 

Heat Regulation of the Body. During heavy exercising, 
as in running, boxing, hoeing, or plowing, more heat is pro- 
duced in the blood by reason of the rapid oxidation in the 
body cells. Nature, at once, sends the blood to the skin 
to be cooled by contact with the air. The sweat glands help 
by pouring out over the surface of the body a {i sweat." 
This evaporates quickly into the air $nd the blood is 



240 PHYSIOLOGY, HYGIENE AND SANITATION 

cooled, very much like air about a house may be cooled by 
sprinkling the grounds with water. 

During cold weather, the blood may become chilled and 
it becomes necessary to save heat. The nervous system 
sends out a message to the tiny blood vessels under the 
skin to contract and the blood is forced away from the 




A A 



Fig 



121.— Section of skin showing (A) hairs. (B) 
Sebaceous glands. 



surface of the body into the deeper tissues where it may 
retain its heat. Thus it is, that in hot or cold weather, 
during a period of rest or exercise, the body heat is kept at 
one even temperature. In health the body temperature is 
maintained at 98 3/5° F. 

Sickness and Body Temperature. During illness often 
the temperature of the body reaches 103 or 104°. Oxida- 
tion is rapid and the skin fails in its task of maintaining an 
even temperature. The person is then said to have a 
fever. 



THE SKIN 



241 




Fig-. 122.— A well kept 
nail. 



Fever is present in all of the acute infectious diseases 
caused by bacteria. A heavy infection of one kind of 
malaria will cause a chill followed 
by a fever. The poison thrown off 
by the malaria causes a rapid oxida- 
tion of tissue cells and the blood is 
sent to the skin to be cooled. The 
sweat glands pour a copious perspira- 
tion over the body and fever soon 
disappears by the cooling of the body. 
The "sweating" in the kind of ma- 
laria which produces the "chill and 
fever" is caused for this reason. 

The nails add beauty to the hands 
and feet. They are useful to protect 

the delicate tips of the fingers and assist in picking up small 
objects. They grow from the layers of skin of their 
under-surface and at their roots, 
(matrix). Care should be used to 
keep dirt from accumulating under 
the nails and around their edges. 

Dirty nails are unsightly and 
may carry infectious matter into 
the body. 

The nails of the toes of the so- 
called civilized people are often 
deformed by the use of ill-fitting 
shoes. 

Summary 

The uses of the skin are for pro- 
tection, for excreting wastes, reg- 
ulating the body heat, and to provide a means for feel 
ing. 




Fig-. 123.— A finger nail 
showing- the matrix. 

A. Seat of growth of 
the nail in thickness. 

B. In length. 



242 PHYSIOLOGY, HYGIENE AND SANITATION 

The epidermis is of varying thickness and is without 
blood vessels, nerves, fat, connective tissue, sebaceous and 
sweat glands. 

Hair, nails, and mucous membranes and hoofs and horns 
•of the lower animals are only modified forms of the skin. 

The heat of the body is kept at one temperature in 
health, regardless of heat, cold, exercise, or rest, by the 
action of the skin through the control of the nervous sys- 
tem. 

Questions 

1. What kind of tissue is the skin ! "Where is it found ? 
What relation has it to hair, nails and mucous membranes ? 

2. Name four functions of the skin. 

3. What is the epidermis? What are its functions? 
What are corns ? Where may they be found ? How may a 
soldier have corns on his shoulders? 

4. How is the epidermis renewed? 

5. Why are complexions of the skin? What makes an 
Indian red and a Chinaman yellow? 

6. What kind of tissues are found in the dermis? What 
are papillae? Where are they most abundant? Why? 

7. What gives to the skin its pliability and toughness ? 

8. Why are hairs furnished for the body? Give three 
illustrations of the use of hairs. 

9. What are sebaceous glands? Where are they? What 
is their function? 

10. Where are the sweat glands? What two functions 
have they ? How do they throw off poisons from the body ? 

11. Why does the blood become hotter during exercise? 
Where is it cooled ? How is it done ? 

12. Why is the skin freer from blood when the body is 



THE SKIN 243 

exposed to cold than it is on a hot day ? What is the func- 
tion of the tiny muscles in the skin? What controls their 
action. 

13. What is the normal temperature of the body? When 
is it increased? 

14. Show how a heavy infection of malaria causes fever. 
How is the fever reduced? What is a chill? 

15. What two functions have the nails? How do they 
grow? Why should they be kept clean? 



CHAPTER XXXIII 

HYGIENE OF THE SKIN 

Hygiene. The skin can do its work best when it is 
kept clean. The impurities of the body, excreted by sweat 
glands, and the w^orn-out cells of the outer skin, if not 
removed, soon give off a disagreeable odor, and form a 
good growing place for germs. Pimples and little "boils" 
over the body are often caused by an unwashed skin. 

Bathing. A cleansing bath for the entire body is 
needed at least twice during the week to keep the body 
free from its impurities and the dust, soot, and dirt. 
Such a bath should be taken at bedtime, using warm or 
hot water and pure soap. The soap aids the water in dis- 
solving and removing the oil from the skin. The hot 
water brings the blood to the vessels in the skin from 
the overworked brain or muscles, so that one becomes 
"sleepy." A hot bath, therefore, is a sedative. 

Sleeplessness, worry, and fatigue often may be re- 
lieved and a good night's rest secured by taking a hot 
bath before retiring. 

Cold Baths contract the blood vessels of the skin and 
drive the blood into the muscles, brain, and internal or- 
gans. It is a stimulant and many people form a habit 
of taking a cold bath every morning to arouse the brain . 
and activities of the body. At once, after the cold plunge 
or "shower," the skin should be rubbed briskly with a 
coarse towel. This stimulates the blood vessels of the 
skin and the blood rushes into them, causing the "red- 
ness" or glow of such a bath. 

244 



HYGIENE OF THE SKIN 



245 




Fig - . 124.— Showing big toe in a 
line with the side of the foot in 
unshod savages. 



The Face and Hands require frequent washing, because 
they are exposed to the dirt of the air and the hands are 
soiled by the work they do. Often the hands pick up 
dangerous bacteria and 
they should be washed 
thoroughly with soap and 
water before eating or. 
preparing a meal. 

The Feet pick up dust 
from the street and while 
at work. Shoes are not 
dust or water-tight and 
the feet become unclean 
quickly and require fre- 
quent cleansing. Very 
often the feet give off a bad odor. This may not be be- 
cause they are not frequently bathed, but because of 
an infection by certain germs which are growing in the 
skin and between the toes. A physician can relieve this 
by ordering an antisep- 
tic for the foot-bath 
and a similar powder to 
be "dusted" into the 
stockings and shoes. 

Hot baths should not 
be taken at once after 
meals because the blood 
will be drawn away 
from the digestive 
organs which need it 

for their work. A cold bath should not be taken when 
one is hot or tired, because the body may become chilled 
too quickly. The work one does and the state of health 




Fig. 125.— Showing natural direction 
of the big toe. (Feet of an unshod 
savagre.) 



246 PHYSIOLOGY, HYGIENE AND SANITATION 



will be the guides for the number and kind of baths one 
may need. 

Clothing. The skin alone, in cold climates and those 
subject to sudden changes in weather, can not keep the 
body heat at an even temperature. Clothing is needed 
to protect the body from injuries, insects, bacteria, and 
to keep the body heat regulated by preventing too much 
or too rapid loss of the body heat. Clothing does not 
"warm" anybody. It simply prevents the escape of heat 

from the body. 
In cold weather 
the cloth should 
be loosely woven 
so that the air 
spaces between 
the threads will 
prevent heat 
from passing 
through. Most 
of our clothing 
is made from 
the hairs of ani- 
mals (woolen 
cloths and 
furs) or fibers 
from plants 
the web of a 




Fig-. 126.— An X-ray picture of feet in shoes. 
A. Showing- crowding of bones in a shoe too 
tight across the toes. B. Showing the proper 
arrangement of the bones in a well-fitted 
shoe. C. Eyelets for lacing shoe. D. WTiere 
bunions often form. 

(cotton or linen) or silk which is 
caterpillar. 

Woolen cloth is best for winter wear because heat does 
not pass through the many openings between its threads, 
or as it is sometimes said, it is a poor conductor of heat. 
Two layers of thin clothing are often warmer than one 
layer of thick clothing because of the layer of " non-con- 



HYGIENE OF THE SKIN 



247 



ducting" air between them. Newspapers folded over the 
chest under the coat are often used by travelers to keep 
them warm. The papers make several layers of air 
through which the heat from the body has difficulty in 
escaping. 

When clothing becomes wet, the air spaces are filled 
with water instead of air, and it then permits the body 
heat to escape, and the body becomes chilled. It is for 
this reason that the body should be at once freed from 
wet clothing, rubbed dry until it is all 
aglow and clothed with dry clothing. 
If this is not done the germs of colds, 
influenza, pneumonia, or other like dis- 
eases may take advantage of the low- 
ered body resistance and produce dis- 
ease of the air passages. 

Linen and Cotton clothes are cooler 
in summer because the woven cloth 
does not contain air spaces that will 
hold the body heat and it is allowed to 
escape quickly. 

A Change of Clothing worn next to 
the skin should be made often enough 
to keep the skin free from its impuri- 
ties. It should be changed after each 
cleansing bath, otherwise the animal matter in the body 
wastes will soon decompose and give off a foul odor. 

-Tight-Fitting clothing should not be worn over the 
chest or abdomen because of its interference with the 
breathing and the work of the digestive system. Tight 
shoes are often the cause of cold feet because the flow 
of blood through the feet is obstructed. If the legs are 
not warmly clad, the feet may become cold because the 




Fig-. 127. —The 
"track" made by 
a flat foot. 



248 PHYSIOLOGY, HYGIENE AND SANITATION 




Fig-. 128.— Flat-foot. Note the in- 
step has almost disappeared. 



blood vessels of the legs contract and a reduced amount 
of blood is supplied the feet. 

Shoes. A great deal of unnecessary pain and discom- 
fort are the result of ill- 
fitting or improperly built 
shoes. The high "peg 
top" heel of many shoes 
for women is a fool- 
ish device of shoe makers, 
for such shoes make 
women walk "On their toes 
instead of their feet. 
Many of the men's shoes 
are pointed and curved 
out of the shape of the 
natural foot. As a result more than one-half of the men 
and women have corns on their feet and suffer from flat- 
feet and the pains of over-strained muscles and nerves. 
Many of them have painful swollen joints on their feet 

or "bunions." Shoes 
should have low, broad 
heels and a sole broad 
enough to cover the 
bottom of the foot, 
without squeezing the 
toes. 

Flat Feet are often 
caused by wearing 
shoes ill-fitting and too 
tight. The bony arch of the foot becomes flattened and 
the muscles of the leg are strained in their effort to sup- 
port the weight of the body while walking or standing. 
Many recruits of the army were discharged because their 




Fig. 129.— A metal arch that often 
will relieve the distress caused by 
a flat foot. 



HYGIENE OP THE SKIN 249 

"flat-feet" would not permit them to stand the hard 
training. 

It is called "flat-foot" because when standing the foot 
lies flat all the way across on the inner side of the foot. 
Certain exercises, as running, playing tennis, tip-toeing 
may strengthen the muscles and help restore the fallen 
arch. A metal support worn in the shoes often gives much 
relief. 

Summary 

A skin to be healthy must be clean and cleansing baths 
are needed to free the body from accumulated dust, dirt, 
soot, and the excretions from the skin. 

Hot baths are sedatives and cold baths are stimulants. 

The functions of clothing, aside from their safe- 
guarding of the sense of decency, are to protect the body 
from external injury and to help the skin regulate the 
body heat. Woolens are best for winter wear because 
they are "non-conductors" of heat; linen and cotton, 
for summer wear because they permit the escape of body 
heat. Wet clothing becomes a conductor of heat and 
when worn, may cause a disease of the air passages by 
the sudden lowering of the body's resisting power 
through loss of body heat. 

Shoes should be built to fit the foot and feet should' 
not be deformed to fit the shoes. Flat-feet, corns, pain, 
and an awkward gait are often the penalties paid by 
wearers of ill-fitting or improperly made shoes. 

Questions 

1. Why should the skin be kept clean? What some- 
times is the cause of pimples and .boils in the skin? 



250 PHYSIOLOGY, HYGIENE AND SANITATION 

2. How often does the entire body need a cleansing 
bath? How should it be taken? What is the advantage 
in using soap ? 

3. How may sleep often be induced when one is tired? 
Why? 

4. What is the effect of a cold bath? When should it 
be taken? How? When should it not be taken? Why? 

5. Should a hot bath be taken just before or after a 
meal ? 

6. Why should the hands be washed before eating or 
preparing a meal? 

7. Why should the feet be washed often? What is 
many times the cause of kl smelling feet?" How may 
they be relieved? 

8. What should guide one in the choice of the kind 
and frequency of baths ? 

9. What three functions does clothing preform? Do 
clothes "warm" the body? Why are they worn in cold 
weather ? 

10. Why is woolen clothing warmer than cotton, linen 
or silk, in cold weather? How may newspapers be used 
to keep one warm? Why? 

11. Why may two thin garments be warmer than one 
thick one? 

12. What is meant by woolens being a "poor con- 
ductor of heat?" When may the same clothing become 
a good conductor of heat? 

13. Why should one "change clothes" when they be- 
come soaked with rain? 

14. Why is cotton and linen clothing cooler in sum- 
mer? 

15. Why should underclothing be changed frequently? 

16. Name three evil results of wearing tight clothing. 



HYGIENE OF THE SKIN 251 

17. Why are " peg-top" high-heeled shoes harmful? 
What objection is often found with men's shoes? What 
is a great cause of corns? What is a "bunion." 

18. How should shoes be built? 

19. How may one know a shoe is built correctly? 

20. What is "flat-foot?" What are the symptoms of 
flat-feet? In what two ways may relief be obtained? 



CHAPTER XXXIV 

THE NERVOUS SYSTEM 

It has been shown in the preceding chapters how the 
many organs perform their tasks and how each system 
of the body accomplishes its purpose. 

The heart pumps so often when the body is at rest and 
more rapidly during exercise ; the lungs take in so much 
air and, if a need arises, at once, may commence to in- 
hale greater quantities of air at shorter intervals. The 
stomach and bowels work in harmony and the glands 
pour out their digestive juices just at the right time for 
their use; the kidneys release poisons while other organs 
help them by doing their particular work. 

Every organ and each system seem to do the right 
thing at the right time, and unless one is ill, there are 
no "strikes' ' of the workers of the body. 

The harmony and efficiency of the thousands of opera- 
tions of the human body are not the result of accident. 
Such team work is only possible when there is manage- 
ment and control. 

So we have now come to the study of the nervous 
system, through which every operation of the body is 
directed. 

Not a body sell is made, a motion produced, a particle 
of food assimilated, a heart throb completed, a breath 
of air inhaled, a sweat gland operated unless it is direct- 
ed and controlled by some agent of the nervous system. 

The Brain, the Spinal Cord and the Nerves are the 
chief organs which direct and carry out the work of the 
body. They make up what is called the central nervous 
system. 

252 



THE NERVOUS SYSTEM 253 

Did you ever think what a wonderful machine the 
human body really is? A man succeeded once in making 
an automatic doll that would walk in a clumsy way 
around a circle. When it was placed in a show window, 
great crowds of people gathered around to see it per- 
form and wondered how it was made to "work." How 
much more wonderful are the performances of the living 
body which walks, runs in any direction, dances, sings, 
thinks, works and creates, and scarcely a thought is 
ever given to its work or the controlling power which 
directs it! 

Decide now that you want to reach in your pocket for 
a pencil. What happens? A message was sent from 
your brain, through the arm nerves to the muscles of 
your arm and fingers ; they contracted and carried your 
hand to the proper pocket; your fingers closed on the 
pencil. The arm muscles pulled the pencil from the 
pocket and the job is complete. This was done as a re- 
sult of the action of the will and was a voluntary act. 
Suppose in reaching in the pocket the fingers have been 
stuck with a pin. Before your brain could think to tell 
you to take the arm away, the arm has been ordered, over 
the nerves of the arm muscles, to jerk away from the 
thing which caused you pain. Such an action is an in- 
voluntary act or a reflex action. 

If one bites an apple, it is because a message has 
reached the brain that one is hungry; the brain sends 
a message to the hand to pick up an apple and carry it 
to the mouth and directs the muscles of the jaw to 
pinch a bite from the apple, with the teeth, and to chew 
it into pieces. These are voluntary acts controlled by 
the brain through nerves leading to the muscles. While 
the apple is being chewed, the tongue moves the pieces 



254 PHYSIOLOGY, HYGIENE AND SANITATION 

here and there in the mouth, between the jaws, to help 
reduce them to a pulp, and skillfully dodges the grind- 
ers because it seems to have learned that a bite on the 
tongue is painful. The muscles of the cheeks in response 
to an order from their nerves hold the pieces of apple 
firmly so that the teeth may crush them; the nerves of 
the tongue are busy giving one the pleasant feeling of 
taste, and at once, the salivary glands, responding to a 
message from their nerves, pour out the saliva to help 
digest the fruit. The muscles of the throat are waiting 
for a message from their nerves, ready to seize the 
ground apple and carry it into the stomach. 

The actions of the tongue, the cheek, the salivary 
glands and the throat muscles are not directed by a mes- 
sage from the mind or brain, but by nerve centers in 
the spinal cord or one of its subagents. The brain is 
the " general superintendent'" of the whole work of con- 
trol and most of the routine work of the body is left 
to the spinal cord, and its helpers. 

How the Nervous System Works. Think of a tele- 
phone system in a city. You will recall that there are 
hundreds of wires, stretched from pole to pole, over 
every street. If each of these wires is followed, it is 
seen to enter a home, a hotel, a factory, or public build- 
ing, and each one, finally, ends in a telephone box which 
is fitted so that a message may be received or sent. 

If these wires are followed in the other direction they 
are seen to become thicker and more numerous and, 
finally, a great number are seen to enter into lead tubes 
or "cables" for convenience in carrying so many wires. 
If these cables are followed, they will lead into the tel- 
ephone center or exchange. There a large number of 
girls will be found at work in front of a long desk, fac- 



THE NERVOUS SYSTEM 255 

ing the "switch board/' which presents thousands of 
holes, each of which represents the end of one of the 
wires leading to every part of the great city. Listen to 
what is said: "Hello, Central, give me 1-6-7.' Hundreds 
of such calls come in every minute. The girl picks up 
a "plug," which is the end of the wire, over which the 
request came, and at once the person who "called" can 
give or receive a message. 

In a general way, the work of a telephone system may 
be likened to the work of the central nervous system. 
The tissue cells of the muscles, glands, lungs, arteries, 
liver, heart and every organ of the body may be said 
to represent the telephone boxes in the houses and the 
buildings in a city which have a telephone ; the nerves 
are the telephone wires; the large nerves nearing the 
cord are the cables ; and the brain and spinal cord may 
be likened unto the exchange. Body cells may receive 
and give messages or impulses. A body cell comes in 
contact with a sharp point of a needle, a message is sent 
over its nerve (the wires) to the spinal cord or one of 
its helpers (the exchange). A "connection" is made 
from the cord over the nerves (wires) and the message, 
"jerk away," is flashed to the muscle cells which re- 
ceive the impulse and contract, and body cells are 
saved from further destruction. 

Thousands of messages are received and sent by the 
brain and spinal cord every minute in response to the 
calls from the body cells at work. 

Many thousands of the nerve impulses from the body 
cells are received and answered by the "helpers" or 
"subagents" of the cord. These are collections of nerve 
tissue along the course of the large nerves near the 
cord and are called ganglia (singular ganglion). 



256 PHYSIOLOGY, HYGIENE AND SANITATION 

The ganglia offer a quicker and a shorter route for 
receiving and sending impluses. They are intimately 
connected with the spinal cord and brain and work in 
entire harmony and at their direction. The ganglia are 
concerned mostly with the involuntary actions of body 
cells, as in digestion, secretion, excretion, respiration and 
the circulation of blood and lymph. The ganglia and 
their connections are spoken of as the sympathetic nerv- 
ous system. 

Questions 

1. Name, six functions of the body which are per- 
formed in harmony. Is such harmony in the body's 
work an accident? Why is it possible? 

2. What is the function of the nervous system? Name 
at least ten operations in the body which are controlled 
by it. 

3. What are the principal organs of the nervous sys- 
tem? What is the central nervous system? 

4. Tell of the part the central nervous system takes 
if you walk to the door and return ; if you put your finger 
on a hot iron. 

5. What is a voluntary action? An involuntary action? 

6. Name the voluntary acts performed when an apple 
is eaten. Name four involuntary acts before it reaches 
the stomach. 

7. Describe a telephone system in a city. What is 
the "exchange?" A "cable?" What are the wires? 
Telephone boxes? How' are calls received? Sent? 
Illustrate. 

8. How may the central nervous system be compared 
to a telephone system? What organs correspond to the 



THE NERVOUS SYSTEM 257 

"telephone exchange !" To the " cables !" To the 
wires? To the telephone boxes? 

9. If body cells come in contact with a burning match, 
what is the first, message sent ? How ? Where ? What 
receives this message? What is at once ordered? What 
is almost instantly done? What is the purpose of this 
arrangement in this case? 

10. How many nerve impulses are sent into the brain, 
spinal cord and its assistants every hour? What are ten 
of such impulses? 

11. What is meant by the " subagents ? ' ' The "help- 
ers or assistants" of the spinal cord? What is theii 
name ? What is their function ? How do they work ? 

12. Name five functions of the "Sympathetic Nervous 
System.' V 



Phy.— 9 



CHAPTER XXXV 

THE ORGANS OP THE NERVOUS SYSTEM 

The Brain is one of the largest organs in the body. Its 
average weight is about three pounds. It is oval in shape 




Fig. 130.— The brain as seen from above. (The cere- 
brum). A. Convolutions of right hemisphere. B. 
Convolutions of left hemisphere. 

to fit the cavity formed by the bones of the skull. A 
deep groove running from the front across the top to the 

258 



ORGANS OF THE NERVOUS SYSTEM 



259 



back divides it almost in half, forming the right and left 
hemispheres of the brain. 

Its surface is wrinkled or irregular and the smooth 
ridges are called the convolutions of the brain. 

If it were cut across, the brain substance, of which it 
is composed, is found to be soft and easily torn. The 
outside of the brain is composed of grayish matter which 
includes all of the convolutions. Under the layer of gray 
matter, the larger remainder of the brain is composed of 
white matter. The largest part of the brain occupies the 
front and top of the skull and is known as the cerebrum. 

The brain is made of nerve cells and their fibers or 
branches which, like a net work, 
connect the brain cells with one 
another. Some of these fibers 
enter the brain from the eyes, 
nose, tongue and ears and 
through their aid, one sees, 
smells, tastes and hears. At the 
bottom of the brain and at the 
rear is a smaller division of the 
brain, the cerebellum. 

A great number of nerve 
fibers enter the cerebellum from 
the spinal cord. Many of these 
nerves are used to convey messages to the brain of vol- 
untary movements and for unity of action or purpose. 

The cerebrum is the part of the brain used in thinking, 
willing and remembering. Through it we are conscious 
of what is going on around us. A person whose cerebrum 
is not developed is an idiot. 

Below the cerebellum, the nerve tissue passes out of 
the skull into the hollow tunnel of the spinal column. 




Fig". 131.— A. nerve cell 
with its many branches. 
(Magnified.) 



260 PHYSIOLOGY, HYGIENE AND SANITATION 




Just before it leaves the skull there is 
a portion of it smaller than the cere- 
bellum and larger than the cord called 
the medulla. It is in the medulla 
that the nerve fibers from the cord 
cross to their position in the opposite 
side of the brain. 

If the right side of the brain be in- 
jured, the left side of the body may be 
paralyzed, that is, the muscles of the 
arm or leg cannot receive their 
"orders" to act because the nerve cen- 
ters or cells, which direct them, are pre- 
vented from operating. 

A blow on the right side of the head 
may cause a blood clot to form over the 
brain cells that control the leg, caus- 
ing them to quit their work. The left leg becomes power- 
less to move. If the blood clot is promptly removed 
and the pressure removed from such brain cells, 

they will again work 
and the useless limb 
will again perform 
its functions under 
the orders from the 
rescued brain cells. 
The Spinal Cord. 
The nerve tissue 
after leaving the 
_,, 190 m . ' . ,.. . ■ - skull passes into the 

Fig-. 133.— The brain cut throug-h from " 

end to end. B. Cerebellum Note the hollow Canal in the 
connection of various parts of the 

brain with each other. (A, e, c, d.) backbone and is now 



Fig-. 132.— A nerve 
cell (greatly mag- 
nified and en- 
larged). Note its 
branches are cut 
off. 




OEGANS OF THE NERVOUS SYSTEM 261 



called the spinal cord. In the lower animals it is called the 
" marrow of the backbone/' 

The cord is about a foot and one-half long in the adult, 
and as large as one 's little finger. It is a bundle of nerve 
fibers, in the center of which is gray matter. The outside 
layer of the cord is white matter. 

Two fissures or cracks run from one end of the cord to 
the other, dividing it into two parts which are connected 
in the center of the cord. 

As is passes downward, the cord gives off thirty-one 
pairs of nerves, which are distributed to nearly every part 
of the body. These are called the spjinal nerves. They 
pass out between the bones of the spinal column. 

Each spinal nerve has two roots ; one from the front of 
the cord (anterior root of the gray matter of the cord) 
and the other 
from the back of 
the cord (poster- 
ior root) . The two 
roots soon unite 
to form a single 
nerve, but the 
nerve fibers re- 
main separated as 
do the wires in a 
telephone cable 
and the fibers 

from each root do their particular duty. The fibers from 
the anterior root carry messages for motion and are 
known as the motor fibers ; the fibers from the posterior 
root carry sensation and are known as sensory fibers. 

Such a nerve leading to the fingers, for .example, can 
carry a message to the cord and to the brain of the 




Figr. 134.— The spinal cord. A. Gray matter. 
B. White matter. C. Posterior root of 
a spinal nerve. D. Anterior root of a 
spinal nerve. E. A spinal nerve. 



262 PHYSIOLOGY, HYGIENE AND SANITATION 



weight, the heat or the "feel" of an object, and the same 
nerve can carry the order back to the fingers for the con- 
trol of their movement. Thus do we see that body cells 
may be likened to the "telephone boxes" in a city tele- 
phone system from which messages may be either sent 
or received. 

Nerve Cells differ from most of the body cells because 
they send off tiny branches, reminding one of the 
branches of a tree, which may extend to a distance of an 
inch or more. It is by means of these tiny branches, con- 
necting many cells 
together, that "team- 
work" of the body's 
parts may be done. 
One of these 
branches of a nerve 
cell may extend two 
or three feet from 
the nerve cell. This 
extension is known 
as a nerve fiber. 

The Nerves. A 
nerve is only a col- 
lection of nerve 
fibers or extensions 
from nerve cells. 
These fibers run side by side and are enclosed in a sheath 
or wrapping of connective tissue in which are tiny blood 
vessels to supply them with nourishment. 

Most of the nerves of the body look like glistening 
white threads, and as they pursue their course to supply 
every organ and group of nerve cells they divide and 
send off branches very much like the arteries until 



| y ' iti\'f»5?}^ 


M^t m 


3s 






MffiiM^^^P 7 ' 


1 


^J$vjrk tPf? 






feP 8 










g^fSSm//, 






"u 


iVfxi 






^nA^aai 


\* 


L ^sL / 


-f 










u f r 








wL 










f^n^*-- 


"^ 








qfrt ^ 




pfe 




I2f x" 








rrr 




'^A 




" M / 


\i V 




- jv \J 


\£iiYX\ 


yuz 


iS 


hy 


T\\ P^ 










E* 


KX&yJ^- 


•CX/Cf 






JQJTf 




111® 


H"^ 


?| 


V 


si 


/>tf ' \ M 


r, ~x\ \WA ItlEM 


* C^ < /* 


.min— r— 


* : 


rpi 


j\ "*r 


^Uar™4( f^rff 










QJlfHRTM^^) 1 


. \ 1 . ., 




N - /> Mi.rii. i/nOi li f I 



Fig - . 135.— Nerve cells and their fibers, 
showing how they connect like net- 
work with each other. 



ORGANS OF THE NERVOUS SYSTEM 



263 



their ends become so small they cannot be seen with the 
eye alone. 

Nerves receive fibers from many other nerves as they 
leave the spinal cord. 

Plexus of Nerves. As the spinal nerves leave the cord, 
many times they form a network in which nerve fibers 
from one group of 
nerves are merged 
with fibers of an- 
other nerve. Such a 
collection and dis- 
tribution of nerve 
fibers is called a 
plexus. It is by such 
means that team 
work of the systems 
and their organs is 
accomplished. 

If one throws a 
ball, the muscles of 
the fingers, forearm, 
arm, shoulder, chest 
and back all work in 
unity. If it were not 
for the plexus of 
nerves which make 
it possible for the nerve impulses or messages to these 
groups of muscles to be in order and regular, the act of 
throwing a ball would be a failure. 

The Sympathetic Nervous System is not a separate 
nervous system. It is a part of the general nervous 
system and subject to its control. A plexus is part 
of it. 




Fig - . 136.— Showing- distribution of blood 
vessels and nerves of the side of the 
head and face. The white lines are 
nerves. The dark ones, blood vessels. 



264 PHYSIOLOGY, HYGIENE AND SANITATION 

Ganglia and their connecting nerves complete it. A 
double row of ganglia (collections of white and gray mat- 
ter) is placed on each side of the spinal column and 
branches from the spinal nerves run into them. The 
ganglia connect with each other and send nerve fibers 
to the spinal nerves. 

The function of a sympathetic 
nervous system is to establish a 
close working relation of sympa- 
thy between many of the organs 
of the body. For example, when 
the muscles do heavy work, the 
heart beats faster, the lungs 
breathe more air, the sweat glands 
work, the blood vessels in the skin 
expand, because the nerve mes- 
sages to all these organs are har- 
monized so they may do team- 
work. Imagine what confusion 
there would be if the brain had to 
think to tell each organ what to 
do, when to do and how to do it. 

The sympathetic nervous sys- 
tem looks after all the vital opera- 
tions of the body. Ganglia are distributed in other parts 
of the body to insure quick delivery and reception of 
nerve impulses. 

Summary 




Fig:. 137.— Showing nerve 
connection with a mus- 
cle which acts with the 
aid of the sympathetic 
nervous system. M. 
Muscle. N. Nerves to 
ganglia. C. Connection 
of ganglia with each 
other and other nerves. 



The brain, the seat of the nervous system, weighing 
about three pounds, is divided into the cerebrum and the 
cerebellum. 



ORGANS OF THE NERVOUS SYSTEM 265 

It is the organ with which we think and are made 
aware of sensations. 

In structure, it is made up of nerve cells forming the 
white and gray matter. 

The cerebrum is the seat of the mind and its nerve 
cells control the voluntary movements of the body. 

The spinal cord is a continuation of the nerve tissue 
of the brain. It gives off thirty-one pairs of spinal nerves, 
each having a motor and sensory root. 

Many of them in a plexus give off connecting fibers to 
other nerves to co-ordinate the work of the organs of the 
body. Nerve cells form all the nerve tissue of the body 
and by branching they form a network of communica- 
tion between one another. 

Nerves are bundles of nerve fibers, which are enclosed 
in a sheath. Each nerve fiber retains its identity and per- 
forms its own function. A nerve may carry both sensory 
and motor fibers. 

The sympathetic nervous system is a part of the gen- 
eral nervous system and consists of collections of white 
and gray matter (ganglia), connecting nerves and 
plexuses of nerves. Their function is to co-ordinate the 
work of the various systems and organs of the body. 

Questions 

1. What is the weight of the brain? Its shape? Its 
location? 

2. What forms the left and right hemisphere of the 
brain ? 

3. What are convolutions? 

4. What does brain tissue look like? 

5. What matter forms the convolutions of the brain? 



266 PHYSIOLOGY, HYGIENE AND SANITATION 

6. What matter is most abundant in the brain? 

7. What is the cerebrum? Where is it located? 

8. Of what is the brain composed? How do we see, 
smell, taste and hear? 

9. Where and what is the cerebellum? 

10. What are the chief functions of the cerebellum? 

11. How are we made conscious of events? 

12. What is an idiot? 

13. What is the enlarged portion of the spinal cord 
called after it enters the skull? What curious arrange- 
ment of the many nerve fibers is found here? 

14. If the left side of the brain is injured so that par- 
alysis of the body occurs, which side of the body would 
become useless? Why? 

15. How may a blood clot following an injury, produce 
paralysis? How might such paralysis be relieved? 

16. What is the spinal cord? Where is it? What is its 
length and size? With what does it join at its upper end? 

17. Of what matter is it composed? Where is the gray 
matter found in the cord ? Where is it found in the 
brain? 

18. What are the spinal nerves ? How many are there ? 
How many roots has each ? What function has the fibers 
from the anterior part of the cord? The posterior part 
of the cord? 

19. Illustrate the action of a nerve from the finger. 

20. What is the chief difference between nerve cells 
and other cells of the body? What is the purpose of this 
structure? What is a nerve fiber? 

21. What is a nerve ? What structures compose a nerve ? 
How are nerves distributed to the body cells? How does 



ORGANS OF THE NERVOUS SYSTEM 267 

the nerve, ending in the body cells, resemble the opera- 
tion of a telephone in the home ? 

22. What is meant by a plexus of nerves ? What is the 
need of a plexus of nerves ? Illustrate this need. 

23. What is the sympathetic nervous system? What 
are ganglia? What controls this system? What is its 
function? Illustrate this function. 



CHAPTER XXXVI 

REFLEX ACTIONS AND HABITS 

Voluntary actions start in the brain because the brain 
wills them to be done. Involuntary or reflex actions are 
those caused by impulses which start in the nerves and 
are conducted toward the brain or spinal cord. 

The ganglia, spinal cord and medulla are reflex centers, 
that is, an impulse may reach these structures and an 
action be ordered before the brain has ever received the 
impulse. One may be walking along a path in a field. A 
black, crooked object is seen lying across the path. An 
impulse goes towards the brain carrying the message 
" There is a snake." The spinal cord gets the message 
first and sends back a message through the nerves to 
all the jumping muscles, "Get out of the way of that 
snake, quick!" The body jumps. The brain by this 
time has received the message and acts. The black, 
crooked thing was not a snake. It was only a bent, 
charred stick. At once the brain sends a message back 
to the muscles of the leg, "Proceed, you were mistaken. 
There was no snake ; only a stick that looked like a 
snake, ' ' 

The first jump was a reflex action. The second act of 
stepping over the stick was a voluntary action. 

Nearly all of our acts are reflex, which is only another 
way of saying that "We are largely creatures of habit." 

"We form letters while we write, speak words when 
we talk, move our legs when we walk, wink our eyes at 
the appearance of danger, ride a bicycle, use our knives 
and forks at the table. All of these acts are reflex and 
are the result of habit. 

268 



REFLEX ACTIONS AND HABITS 269 

In the same way, the body may be trained to be erect 
while sitting or standing, to chew food thoroughly; to 
keep the teeth, skin and nails clean; to breathe deeply, 
to exercise daily, to use correct language, to behave 
properly and to perform most of the daily tasks which 
make up our lives. 

Such habits as these are good and by repeating, over 
and over, each of them, the nerve cells become so used 
to ordering them done that the brain finally turns the 
job over to the spinal cord and ganglia, which continue 
to do them through life. 

Bad Habits are formed in the same way. A great 
many bad habits are formed because of neglect. It seems 
so much easier not to do things which should be done 
than to do them. 

Observe which of your friends has teeth that are un- 
clean, decayed and covered with tartar and decom- 
posed food. Such a person has neglected to keep the 
teeth clean. 

It is a bad habit with bad results, which a good habit 
would have prevented. 

Perhaps such a person had been washing the teeth, 
and for some reason one day it was neglected. The 
nerve cells probably reminded the person several times 
during the day that some work was left undone. Another 
time it was easier not to do it, and after a few times 
the nerve cells were so used to this work not being done 
that they no longer urged the muscles to perform that 
task. 

People often sit or stand in a stooped or "humped" 
position, which prevents them from getting as much air 
as they should have and it makes them grow crooked. 
The nerve cells become accustomed to the wrong posture 



270 PHYSIOLOGY, HYGIENE AND SANITATION 

and after a while they offer no protest and give nerve 
impulses for the wrong position to be kept. 

Children often speak incorrectly because they hear 
often such expressions as "I ain't sick/' " Ain't you 
goin'?" "He wuz there," and many others. The nerve 
cells become trained to use them, and many times in 
later life, when one learns to use correct language, much 
embarrassment may be felt because in an unguarded 
moment the old brain cells will order one of these in- 
correct expressions to be uttered by the organs of speech. 

One should learn early to use correct language and re- 
peat the effort often until it becomes a part of the re- 
flex work of the nerve cells. 

Reflex Action and Character. It is through the action 
of the nervous system that character is formed. As we 
think, we are and do. A character is good or bad, de- 
pending upon the training one's nervous system has had. 

Repeated training in doing and thinking right, results 
in the formation of a habit which after a time becomes 
a reflex action and is performed without great effort of 
the brain cells. 

"Sow a thought, reap an action; sow an action, reap 
a habit; sow a habit, reap a character; sow a character, 
reap a destiny." This is a famous quotation, but it illus- 
trates the truth of the action of nerve cells in forming 
a good or bad habit through reflex action. 

"Who will steal a penny in his youth, will steal a 
pound in his manhood," is a proverb that shows a re- 
sult of habit and its effect upon character. 

A child may be taught to tell the truth and that to 
tell a lie is shameful and wrong. The first lie that he 
tells hurts his conscience, but if his training has not been 
good, he may be induced to tell another and another until 



REFLEX ACTIONS AND HABITS 271 

in a few years it seems easier to lie than to tell the truth. 
But it only seems easier, for by forming this habit of 
telling untruths, his character becomes fixed as being un- 
reliable and his friends discredit him, his business asso- 
ciates fear him and he is really much worse off, though 
it may seem to him that lying is easier. 

The habit of thinking or talking of evil things is 
dangerous to one because it is only a step from thinking 
evil to doing it. One would never desire to become a 
drunkard of the streets, or a gambler whom every one 
despises. Such people have that kind of reputation be- 
cause they have repeatedly drunk or gambled until their 
character is fixed by doing them. 

Their first acts were not done, however, until after 
they had thought of doing it, maybe, once and quitting. 
The mind should think only of things which one would 
like to be or do, that will make a respected and honored 
man or woman, and then one will do only things which 
are right and proper and a good character is the re- 
ward. 

Summary 

Voluntary actions result from efferent nerve impulses, 
involuntary actions from afferent nerve impulses. Most 
of the acts of the body are the results of afferent im- 
pulses and are, therefore, reflex actions. Habits are re- 
flex, and they may be good or bad. 

Habits are the result of repeated similar actions of 
performing, at the direction of brain and reflex nerve 
cells. 

Keflex action is the basis of character. One may not 
become a gentleman in a day. The character of person 
is the result of fixed habits. 



272 PHYSIOLOGY, HYGIENE AND SANITATION 

Questions 

1. Where is the origin of voluntary actions? Of in- 
voluntary actions? 

2. Name three reflex centers. What is meant by re- 
flex centers? 

3. Illustrate two reflex actions. Explain why each 
was an involuntary action. 

4. What is meant by saying, "We are creatures of 
habit ?" 

5. Name ten actions that become reflex after continued 
practice, which at first were voluntary. 

6. Name seven good reflex actions that one should 
form to preserve health. 

7. How are good habits formed? Bad habits? Give 
illustrations of three bad habits. 

8. Why should one learn early the habit of using cor- 
rect language? 

9. How is character formed? Why is one's character 
good or bad? 

10. What has reflex action of the nervous system to 
do with formation of character? 

11. What famous quotation shows the relation of re- 
flex action and habit to character? 

12. What wise proverb shows the result of a bad habit ? 

13. How is the bad habit of lying formed? Is it 
easier to lie than to tell the truth? Why? 

14. What danger is there in evil thoughts and talk? 

15. What is the rule for forming a noble character? 



CHAPTER XXXVII 

HYGIENE OF THE NERVOUS SYSTEM 

The nervous system is responsible for all the activi- 
ties of the body. It is of the greatest importance to keep 
it in health. If it suffer, the work of all systems and 
organs of the body is impaired. 

Exercise, good food and air, and regular habits are 
as necessary to keep the nerve cells in health as they are 
to keep any of the other body cells well. 

Rest and Sleep. The body cells cannot work all the 
time. They must rest. After hard muscular exercise, 
rest is necessary. The brain, too, becomes tired from 
hard thinking and from its work of directing the move- 
ments of the muscles, and it must rest to be ready for 
the next day's work. 

Sleep is the state of the body during which all volun- 
tary impulses are suspended and the brain ceases to re- 
ceive and record sensations. Consciousness is lost dur- 
ing sleep. It is at this time that weary brain cells take 
up nourishment from the white blood cells and recover 
their energy for work when the brain is aroused from 
sleep. 

The vital processes, as breathing, the circulation, and 
secretions are kept in operation through the reflex cen- 
ters of the sympathetic nervous system. 

Babies should sleep about eighteen hours of the day; 
children from the age of five to fourteen should sleep 
about twelve hours, and adults about eight hours of each 
day. 

Nothing tires one so much, or impairs the health so 
greatly as the continued loss of sleep. "Keeping late 
hours" has long been known as the cause of early decay. 

273 



274 PHYSIOLOGY, HYGIENE AND SANITATION 

Tobacco. The use of tobacco in any form is injurious 
to the nervous system in many ways. The effects of 
tobacco on the muscles through the nervous system are 
such that they tire easily, and cannot maintain contests 
of endurance. "Unsteady nerves" is an old expression, 
and only another way of saying that the nerve control 
of muscles has been impaired. Tobacco causes unsteady 
nerves, and a "tobacco heart" is caused by interfer- 
ence with the action of the nerves which supply the heart. 

The effect on the mind of the use of tobacco is pro- 
nounced. As a rule, students who use tobacco habit- 
ually have greater difficulty in making as good a show- 
ing as others in the same class who do not use tobacco. 

Cigarette smoking among younger pupils always pro- 
duces mental dullness and their nervous system is af- 
fected in many ways. Body cells do not multiply so 
rapidly and the growth of their bodies is stunted many 
times. 

The evil effects of cigarette smoking have been so well 
recognized that many states have forbidden their sale 
to young people. Most of the evil effects of tobacco 
on the various organs of the body are due to the hurt- 
ful influence of the poison on the nervous system. 

Tobacco poison acts directly on the nerve cells, caus- 
ing stimulation followed by fatigue. The use of tobacco, 
especially by young people, creates a false mode of life. 
They often are restless, nervous, irritable, "hard to 
please," and usually selfish. Tobacco, therefore, in- 
fluences the formation of character and the habits it en- 
courages are usually not of the best kind. 

Alcohol. In the preceding chapters attention has 
been called to the evil effects of alcohol on various organs 
and body cells. Its effects on the nervous system are ap- 



HYGIENE OF THE NERVOUS SYSTEM 275 

parent to everybody who has observed one under its 
influence. 

A drink of whiskey, wine or beer, in one who has 
not formed a habit causes a giddy feeling in the head. 
The person often indulges in fast and foolish conversa- 
tion, but he imagines he is saying " smart " things. His' 
muscles may be very active from the nerve impulses 
which they are receiving. After a little while the mind 
begins to be dull, and drowsiness appears. These effects 
show there has been a powerful effect on the brain cells. 

The brains of animals have been examined after they 
have been given enough alcohol to make them " drunk." 
When examined, it was found that the nerve cells were 
shrunken in size and that many of the connecting 
branches of the cells were injured and almost destroyed. 

Long continued use of alcohol destroys brain cells and 
renders them less useful. The power to think is de- 
creased and the will power is usually weakened. 

Its effect on the development of character is very bad, 
for many times a person under the influence of alcohol, 
with the will weakened, will do a great many wrong 
acts which, when free from the effects of alcohol, would 
be repulsive and disgusting to his better nature.. 

Probably the worst effect of alcohol on the nervous 
system is that it leaves a "craving" or "appetite" for 
more, and as its use is continued, the will power is still 
further weakened and the appetite increased in its de- 
mands. 

It is a familiar but sad recollection to think of some 
young person who, in an evil hour, took his first "drink," 
and from year to year the number and quantity of his 
drinks increased until, in the prime years of his life, 
he became a habitual drunkard. 



276 PHYSIOLOGY, HYGIENE AND SANITATION 

Alcohol is a poison to the nervous system and in no 
way may it be considered a food. Its use in the world 
for a beverage is fast disappearing and many states and 
countries have prohibited, by law, its sale and manu- 
facture. 

Employers of labor which requires a "steady hand 
and a cool head" are refusing to employ or retain in 
their employ men who use intoxicating liquors. 

The records of courts, houses of reform, and the evils 
of society are heavy with the evidence that intoxicating 
liquor is a cause and companion of a large per cent of 
the crimes and moral wrongs of society. 

Summary 

The care of the nervous system is important to main- 
tain the efficiency of all of the organs and systems of 
the body. 

Sleep is the rest period for the nervous system. It 
should be secured every day at regular hours for periods 
of eight to eighteen hours in twenty-four for infants and 
adults. 

Tobacco is a nerve poison and persistently used has 
a weakening effect on the mind and muscles. 

Alcohol has a disastrous effect on nerve cells and the 
mind and tends to weaken character. It creates an ap- 
petite for itself and weakens the will power for resist- 
ing its demands. Its use is being rapidly prohibited 
by law and it plays a large part in the commission of 
the sins of society. 

Questions 

1. Why is it important to keep the nervous system in 
health ? 



HYGIENE OF THE NERVOUS SYSTEM 277 

2. Name three rules of hygiene for helping to keep 
it in health? 

3. When do nerve cells get most of their rest? 

4. What is sleep? How much sleep should babies 
have? Children aged six to twelve? Adults? 

5. What is the harm in keeping "late hours'' and 
losing sleep? 

6. Name two evil effects of the use of tobacco on 
muscles through the nervous system? What are "un- 
steady nerves ?" What is the cause of "tobacco heart-?" 

7. What bad effects may the use of tobacco have upon 
the mind? What special harm does cigarette smoking 
have on young people? 

8. How may the use of tobacco in youth affect char- 
acter? Why? 

9. What is the effect of a drink of alcohol taken by 
one who is not "used to it?" What damage has been 
found to nerve cells of animals which have been made 
"drunk" on alcohol? 

10. What is the effect of long continued use of alcohol 
on brain cells? On the will power? On character? 
Why? 

11. How does one become a "drunkard?" 

12. Why do not employers of labor secure or retain 
men who indulge in the use of alcoholic beverages? 
What is the relation of intemperance in the use of alco- 
hol to crime and social evils? 



CHAPTER XXXVIII. 

THE SPECIAL SENSES 

All of our knowledge comes from our experiences which 
are recorded in the brain. They are gained by our sen- 
sations. 

We have experienced the sensations of heat, cold, hun- 
ger, thirst, illness, weight and pressure. 

There are five special senses which furnish us with all 
our knowledge of objects outside of the body. They are 
feeling, tasting, smelling, hearing and seeing. 

If a man were to lose the power of all of these senses, his 
mind would soon stop thinking and it would be perfectly 
blank. The loss of one's sight or hearing, or speech is a 
fearful one and the knowledge and experience of one so 
afflicted are limited. 

All of these special sensations are perceived by the brain 
through an arrangement of sensory nerve fibers located in 
special organs. Thus, the sense of tasting is in the tongue ; 
smelling in the nose; feeling in the skin; hearing in the 
ears, and seeing in the eyes. 

The Sense of Feeling is located in the skin. It is most 
developed in the tips of the fingers, on the lips, and tip of 
the tongue. Tiny nerve endings are found in the papillae 
of the skin and when these are brought into contact with 
an object, they carry to the brain impulses which produce 
sensations of pain, shape, size, weight, heat, cold, and de- 
gree of hardness and smoothness. 

One of our first desires upon seeing a new object is to 
"feel" it, for it is impossible to judge of its weight, con- 
sistency or temperature by sight alone. 

278 



THE SPECIAL SENSES 



279 



Pain is one of our most useful of sensations, for by it the 
body is often protected against injury. "Without this sen- 
sation, the hand might be laid upon a hot stove and be 
severely burned be- 
fore it would be 
removed. Pain at 
once sounds the 
alarm and the 
body cells are sav- 
ed by reflex action. 

The pain of 
toothache, illness 
and of errors in 
eating or drink- 
ing, likewise, may 
b e considered a 
blessing, because 
it calls attention to 
a condition which 
ought to be correct- 
ed. The cause of 
pain and not pain 
itself is to be 
avoided. 

Taste. The touch nerves are distributed over all the 
body, but the special touch nerves which carry the mes- 
sages of taste are located only in the tongue. 

The taste nerves have special endings in the outer lay- 
ers of cells of the tongue, called taste buds. A substance 
to be tasted must first be dissolved. The liquid containing 
such substance carries it between the taste cells, and a 
special impulse is carried by the sensory nerve to the 
brain. If the tongue be wiped dry and a bit of sugar be 




The tongue, the organ of taste. 



280 PHYSIOLOGY, HYGIENE AND SANITATION 



placed upon the tip of the tongue, it will not be i ' sweet " 
until the saliva has dissolved it and carried it between the 
taste cells. The sensation of taste may be sweet, sour, bitter, 
or salt. 

Sweet substances are best tasted on the tip of the tongue, 
while bitter ones are tasted most on the sides and back 
of the tongue. 

The sense of taste is useful; it acts as a guide in the 
selection of our food, and protects the body from food 
which might contain dangerous poisons; It may, like- 
wise, be abused for often too much food is eaten because 
it tastes good. Spices and stimulants to the sense of taste 
are to be avoided for this reason. 

Smell. A special pair of nerves supply the mucous mem- 
brane of the front part of the nose with nerve endings 
which carry impulses to the brain, which produce the 
sensation of smell. These endings lie between the cells of 
the mucous membrane and branch out into fine hair-like 
endings. These nerve endings are called the olfactory cells. 

A substance can only be smelled when it gives off into 
the air tiny particles (molecules) of itself. When this air 
enters the nose in inspiration, these tiny particles come in 
contact with olfactory cells and the impulses are carried to 
the brain. Sensations of smell are usually spoken of as 
pleasant, foul and pungent. 

The sense of smell may be made more active by "sniff- 
ing" the air into the nose, which brings air in contact with 
a larger surface of mucous membrane containing olfactory 
cells. 

The Uses of Smell are important. Foul, dangerous, or 
impure air in a room or neighborhood may be detected by 
the sense of smell. Decayed food often gives off a bad odor 



THE SPECIAL SENSES 281 

which the nose is quick to detect and such food is refused 
admittance into the stomach. 

The odor of many foods is quite agreeable and adds to 
the pleasure of eating and thus promotes digestion of 
food. 

Care of the Nose. Olfactory cells if once destroyed are 
never replaced. It is important to avoid breathing dust or 
irritating gases of certain trades because they cause irri- 
tation and inflammation of the mucous membrane of the 
nose, which often results in its destruction and impairment 
of the sense of smell. "Picking" the nose with the fingers 
is unsafe for it often damages the delicate lining of the 
nose, causing the blood to flow and infects it with bacteria 
which are always found under the finger nails. The dried 
accumulations in the nose are the result of inflammation 
of the mucous membrane (catarrh) and they should be 
softened with pure vaseline and removed by "sniffing" 
into the nose a bit of warm salt-water made by dissolving 
a teaspoonful of salt to the pint of water. 

A catarrh of the nose should be treated under the di- 
rection of a physician for its continued attack often leads 
to impairment of the sense of smell and other serious con- 
ditions. 

Summary 

The source of all of our knowledge is in the exercise of 
our organs of special sense in feeling, tasting, smelling, 
hearing and seeing. 

Nerve endings in the skin are the organs of feeling by 
which form, weight, consistency, temperature, and size 
of objects are perceived. Pain is a danger signal and is 
of great value for protecting the body from accidents, de- 
cay and illness. 



282 PHYSIOLOGY, HYGIENE AND SANITATION 

The sense of taste is in the nerve endings of the tongue, 
which are stimulated by the solution of substances which 
have taste. Taste is of value in the selection and apprecia- 
tion of foods. 

The sense of smell is located in the front part of the 
nose where the olfactory nerve spreads its tiny branches in 
the mucous membrane. The sense of smell adds to our 
pleasures and is of value in the detection of impure and 
dangerous air and food. 

Questions 

1. What is the source of all of our knowledge? Name 
seven general sensations that all of us have experienced. 

2. Name all of the special senses. What would happen 
to one's mind, if all of the special senses were lost? 

3. How does the brain perceive these special sensations? 

4. Name the organs of the five senses. 

5. Where is the sense of feeling located? How do we 
feel? What knowledge is gained by feeling? Why do we 
desire to feel an object? 

6. What is pain? What is the value of pain? Illustrate 
this value. 

7. Where is the sense of taste located? How do we 
taste ? Is dry sugar sweet ? When is it sweet ? 

8. What is the value of the sense of taste? 

9. What is the organ used for smelling? What part of 
it is used for this purpose? How do we smell? Why do 
bird-dogs " sniff the air' 7 when on a hunt? 

10. Name four uses for the sense of smell. 

11. How may the sense of smell be impaired ? 

12. What is the danger of "picking" the nose? What is 
' ' catarrh ' ' ? How should it be treated ? Why ? 



CHAPTER XXXIX 

HEARING 

Next in importance to the sense of sight is hearing. 
By hearing is meant the sensation made by impulses in 
the brain cells which are stimulated through a special 
pair of nerves (the auditory) by sound waves of the 
air. 

The air is a mixture of gases, and it is always in mo- 
tion. Every movement that is made creates a wave-like 
movement in the air. If a room contains smoke, and the 
arm is waved, the motion of the air may be seen in the 
movement of the smoke. Such a motion of the arm pro- 
duces no sensation of noise in the brain. If, however, 
the top of a table is hit a quick, hard blow with a thin 
board, a noise is heard, because the air has been dis- 
turbed so greatly that its waves have made an impres- 
sion on the nerves of hearing. 

When a stone is thrown into the water, waves are 
made which start at the point where the stone enters 
it, and are spread in widening circles as the impulses of 
each wave come in touch with water farther away, and 
push it along with gradually decreasing force. The 
waves finally become so wide and shallow that they can 
no longer be seen. 

Waves of air act in very much the same way. If a 
book is dropped on the floor, at once waves of air are 
made in all directions and such waves are greatest near 
the point where the book fell, and as they travel through 
the air, the waves finally become wider and more faint 
until the sound can no longer be perceived. 

283 



284 PHYSIOLOGY, HYGIENE AND SANITATION 



The firing of a great gun produces waves of such force 
in the air that often the ears of a gunner are severely 
injured. Several miles away these waves become so faint 
that scarcely a sound is heard. 

Sound can be heard if there are at least sixteen air 
waves in a second but it will have a low pitch. 

As the number of air waves increases in each second, 
the sound becomes higher in pitch. A scream of a voice, 

or the sound of a 
shrill whistle, is 
caused by very rapid 
movement of air 
waves, and when the 
number of such 
waves exceed 40,000 
per second, sound 
can no longer be per- 
ceived. 

Pitch in sound, as 
in music or talking, 
depends upon the 
rapidity of move- 
ment of air waves or 
sound waves which 
reach the ear. 
The Organ of 
n.- - -km- ' n». * i * ^ i* a Hearing is the ear, 

Fig-. 139.— The external ear. A. Folded ° ' 

cartilage. B. Tiny muscles. C. Open- one on eac h s i(J e f 
mg into auditory canal 

the head. Each ear 
is made up of three parts ; the external or outer ear, the 
middle ear; and the internal ear. 

The Outer Ear is a peculiarly folded piece of cartilage 
covered by skin, and a tube or canal (auditory) which 




HEARING 285 

leads to a whitish membrane (tympanum) stretched 
across it like the head of a drum. The tympanum is com- 
monly called the "drum" of the ear. 

The function of the external ear is to catch the waves 
of sound and carry them to the drum. Its shape reminds 
one of a horn with a large opening leading to the audi- 
tory canal. Persons who are slightly deaf often insert 
a large metal horn into the ear to assist it in catching 
more of the sound waves. 

The auditory canal is kept soft with a kind of wax 
secreted by the skin. 

The Middle Ear is a hollow in the bone (temporal) in 
which are three tiny bones joined together, forming a 
chain. One end of the chain is attached to the drum, the 
other reaches to the internal ear. On account of their 
shape these bones have been called the hammer, anvil, 
and stirrup. The three of them would weigh no more 
than a small grain of wheat. From the middle ear a tube 
runs to the back of the throat (the Eustachian tube). 
Its function is to admit air into the middle ear so that 
the air pressure on each side of the drum may be the 
same. If unequal air pressure exists, the action of the 
three bones is hindered and defective hearing is the re- 
sult. 

"When one dives under water, a bit of deafness is often 
noticed upon reaching the surface. If one "swallows," 
this feeling at once disappears because air has entered 
the middle ear from the back of the throat and the air 
pressure is made the same on each side of the drum. 

At times, following "colds," la grippe or similar in- 
fections, the Eustachian tube becomes closed, with im- 
pairment of hearing, and it may become necessary to se- 
cure the services of a physician to open it again. 



286 PHYSIOLOGY, HYGIENE AND SANITATION 



The Internal Ear lies in a cavity deep in the temporal 
bone and is entirely filled with fluid in which are the 
tiny ends of the auditory nerve. The fluid is prevented 
from escaping into the middle ear by a tough, thin mem- 
brane. 

The internal ear is about seven-eighths of an inch in 
its entire length and for convenience is described in 
three parts: The middle part (the vestibule) connects 
with one of the bones of the ear (stirrup), which is at- 

tached to a thin, tough membrane. 

The front part (the cochlea) is 
shaped like a snail shell. It is in 
the cochlea that the auditory 
nerve divides into tiny, hair-like 
ends which receive the impulses 
caused by the sound waves. The 
remaining part (the semicircu- 
lar canals) is made up of three 
loops, each of which is filled with 
fluid. These canals aid one in 
keeping his balance through re- 
flex action of the muscles. If one turns around rapidly 
several times, he becomes " dizzy." It is caused, most 
likely, by a disturbance of the fluid in the semicircular 
canals. 

How We Hear. The waves of sound enter the exter- 
nal ear and strike the ear-drum which is made to vibrate 
exactly as a head of a drum which is beaten with a stick. 
The drum, attached to one of the tiny bones (the ham- 
mer) causes this bone to move to and fro and this mo- 
tion is carried along the chain of bones to the ''stirrup'' 
which is attached to the membrane of the internal ear. 
The movement of this membrane sets in motion the fluid 




Fig-. 140.— The internal 
ear. A. The vestibule. 
B. The cochlea. C. The 
semicircular canals. 



HEARING 



287 



of the internal ear, which stimulates the delicate hair- 
like ends of the nerve of hearing. These nerve impulses 
are carried to the brain and a sensation of noise is pro- 
duced. What a wonderful piece of machinery is this 
delicate arrangement by which noises ranging from the 
roar of cannon to the sweetest notes of music may be 
recorded in the brain! 

Care of the Ear. Sometimes wax accumulates in ex- 
cess in the external canal and may cause a dry cough 
and slight deafness or pain in the ear. It should not be 
removed with a pin or other hard substance for the skin 
may become infected or the drum may be injured. It is 
best to 
have it re- 
moved by 
a physi- 
cian. 

The mid- 
d 1 e ear 
often be- 
comes in- 
flamed fol- 
lowing 

colds and like infections, and "earache" results. It is 
very painful and unless hot flannels applied to the side 
of the head relieve the pain in a few hours, a physician 
should be called. 

"Running ears" are the result of an inflammation in 
the middle ear, which has produced an abscess. The 
accumulated pus has burst the drum membrane and the 
loss of hearing may result if it is not properly treated 
under the direction of a good physician. 

Sometimes this inflammation spreads into the bone be- 




Fi£ 



141.— Testing- the hearing- in pupils by the use 
of a watch. 



288 PHYSIOLOGY, HYGIENE AND SANITATION 

hind the ear causing intense pain and high fever. An 
operation is then most often necessary to chisel through 
the outer layer of bone and free the pus. 

Loud and unexpected noises should not be produced 
close to the ear, for such sound waves may impair the 
delicate structure of the ear or even rupture the drum 
membrane. 

Summary 

Hearing is the sensation produced in brain cells 
through the auditory nerves which are stimulated by 
sound waves through the ear, the organ of hearing. 

Sound waves vary in intensity depending upon the 
number of vibrations per second, and produce a noise 
of low, medium or high pitch. 

The external, middle and internal ear are intimately 
connected so that sound waves are received, transmitted 
and regulated for their reception by hair -like ends of 
the auditory nerves. 

The ear, being a delicate and complex piece of ma- 
chinery, should not be neglected when inflamed or in- 
jured but- at once should be treated by a physician, skilled 
in its care. 

Questions 

1. What is hearing? What is the nerve of hearing? 
What is noise? 

2. Why does not a motion of the arm produce a noise? 
Why does the ringing of a bell make a noise? 

3. Explain the action of water when a stone is thrown 
in it. Explain the action of air when a gun is fired. Why 
can not a sound be heard at any distance? 



HEARING 289 

4. What is the least and greatest number of vibra- 
tions of air that produce sound, which the human ear 
can detect? What is pitch] 

5. What are the organs of hearing! What is the ex- 
ternal ear? What is the tympanum: What is its com- 
mon name? What is the shape of the external ear? Why? 
What is the use of all the "wrinkles" in the outer ear? 

6. What is the purpose of "ear wax?" How may it 
produce trouble? 

7. What is the middle ear? What does it contain? How 
large are the bones of the middle ear? 

8. What is the Eustachian tube? What is its purpose? 
Illustrate its use. 

9. How do colds and la grippe of 'en affect hearing? 
How may relief be obtained through a physician? 

10. What is the internal ear? With what is it filled? 
How many parts has it? How is it connected with the 
middle ear? 

11. What is the cochlea? What is its function? 

12. What are the semicircular canals? What is their 
function? Illustrate this. 

13. Explain how one hears. 

14. What three bad effects may an accumulation of 
wax in the ear produce? What is the remedy? 

15. What is "earache?" What is the cause and danger 
of "running ears?" Can an ear "run" unless the drum 
is ruptured? Why? What serious result may follow an 
abscess in the middle ear? 

16. How may sudden and loud noises affect the ear? 



CHAPTER XL 



SEEING 



Probably the most serious misfortune which might 
befall a person would be the loss of sight, A person who 
is blind is in darkness all of the time. Familiar scenes, 
the reading of books, and the recognition of the faces 
of friends and loved ones are lost forever. 

The organs of 
sight are the eyes, 
which are located 
in the bony 
sockets of the 
skull. 

The Eyelids. 
The upper and 
lower eyelids pro- 
tect the delicate 
membranes of the 
eye and on their ' 
edges are rows of 
curved hairs 
which prevent 
much dust and 
foreign matter 
from entering the 
eye. The inner surface of the lids and the surface of the 
eye which they cover are kept moistened with a fluid, 
the tears, 

The tears are secreted by the lachrymal glands which 
are just under the bony ridges at the outer end of the 
eyebrows. 




Fig\ 142.— The eyeball protected by its bony 
socket in the skull. A. Eyeball. B. Bonps 
of the skull. C. Muscles of the eye. D. 
OiDtlc nerve. 



290 



SEEING 



291 



The Eye is a spherical shaped body about one inch in 
diameter. It is almost round like a marble, except at the 
front side where its surface bulges out. It is surrounded 
by a mass of fat, muscles, and connective tissue and 
moves freely by the action of its muscles. 

Six muscles move the eyeball, one is attached at its 
upper and lower sides and one at its inner and outer 




Figr. 143.— The eyeball viewed in front. A. Muscles to 
move the eye up, down, in and out. B. Muscles to 
roll the eye. C. Iris. D. The pupil. E. Union of 
the sclerotic coat and cornea. 



sides and two are so attached that the eyeball can be 
rotated or turned in any oblique direction. 

It is by action of these muscles that we look up and 
down, sidewise, either in or out, or roll the eyes 
around. 



292 PHYSIOLOGY, HYGIENE AND SANITATION 



The eye in front is provided with a window through 
which the light enters. It is a perfectly transparent mem- 
brane (cornea) and it joins the white membrane (sclero- 
tic) of the eyeball. 

The " color of the eyes' 7 is due to the coloring matter 
in the curtain (iris) which is seen just inside the eye. 
The pupil is the round hole in the curtain and it admits 
light into the deeper parts of the eyeball. The pupil 

sometimes is 
large and 
again small. 
In very 
bright sun- 
light the 
pupil is least 
and in dark- 
n ess it is 
largest in 
size. The 
function of 
the iris , 
which is sup- 
plied with 
tiny muscles 
to regulate 
the size of 

the pupil, is to admit just enough light into the eye to 
see best. If the eyelids are closed for half a minute and 
suddenly pulled open, the pupil may be seen to become, 
at once, smaller. 

Between the cornea and the iris there is a small 
chamber filled with a perfectly clear fluid, the aqueous 
humor. 




Fig-. 144. — A cut through the eyeball from the 
front to the rear and from above down. A. 
Cornea. B. Chamber for aqueous humor. C. 
Iris. D. Lens. E. Space for the vitreous 
humor. F. The retina. G. The optic nerve. 



SEEING 



293 



Just back of the pupil is a lens which, like one in a 
camera, is used to bring all the rays of light entering the 
eye to one point. 

The lens (crystalline lens) permits the light to pass 
through, and by the action of its tiny muscles, its shape 
can be so changed that the rays of light will be brought 
together at one point. Have you ever used a reading 
glass to burn a hole in a paper by holding it towards 
the sun and moving it back and forth until the light 
would all be in one bright, fiery spot? The lens of the 
eye works very much in the same way. If we look at 
this page and at once look across the room, there will 
be noticed a change 
of some sort which 
occurred in the eye. 
The change consisted 
in the action of the 
muscles of the lens 
which changed its 
shape so that the 
rays of light were 
brought to one point 

(a focus) in the back of the eyeball. The lens is made 
thicker to see objects near the eyes, and its muscles must 
make it thinner to see objects farther away. 

The eyeball is filled back of the lens with a thick, dark 
colored fluid (the vitreous humor). At the rear of the 
inside the special nerve of sight (optic) enters the eye- 
ball and spreads out in a wonderful network of fine 
branches which form the inner coat (retina) of the eye. 

How We See. Have you ever thought what light is? 
It is by means of light that we see. Xo one can see in 
absolute darkness. 




Fig. 145.— Showing- how a lens brings 
parallel rays of light A, B, P, C. D, to 
a focus as at P. 



294 PHYSIOLOGY, HYGIENE AND SANITATION 

Ether is the name of a substance which fills all empty 
space. It is between the molecules of air, wood, stone and 
steel. It reaches the moon, sun and stars. Light is the 
waves of ether in motion. "When we look at a burning 
match, or any object, the waves of ether are in mo- 
tion and they enter the eyeball through the cornea, pass 
through the pupil of the iris and the lens, which changes 
its form so that the waves of ether (or rays of light) are 
brought to a point (focus) on the tiny nerve endings of 
the retina on the back wall of the eyeball. These waves 
of ether stimulate the nerve fibers of the optic nerve, the 




Fig 1 . 146.— Showing- how the rays of light are focused 
before they reach the retina as in near-sighlejlness. 

impulse is carried to the brain cells and by their action 
we perceive the sensation of sight. 

Near-Sightedness is a defect in the eye which causes a 
blurred or indistinct image. A near-sighted person holds 
the eyes close to the object to be seen. The rays of light 
entering the eye are brought to a focus in front of the 
retina instead of upon it. A competent oculist is often 
able to correct this defect by ordering special lenses of 
glass to aid the crystalline lens in focusing the rays of 
light on the retina. Such glasses or "spectacles" should 
be worn during the working hours. 

Far-Sightedness is a defect in the eye by which rays 
of light are unable to be focused upon the retina because 



SEEING 295 

it is too close to the lens. People who are far-sighted, 
when reading, hold a book far away from the eyes. This 
condition can be corrected by wearing glass lenses of 




Fig - . 147.— Showing- how near-sightedness may be re- 
lieved by wearing the proper glass or lens. 

such a shape that the lens of the eye can bring the rays 
of light to a focus on the retina. 

Astigmatism is a defect of the eye caused by a flattening 
or irregularity in the curve of the cornea. Part of an 
image may be perfectly focused on the retina but the 
rays of light entering at the defect in the cornea are 
imperfectly focused and a blurred image results. A com- 
petent oculist is able to order a glass lens which corrects 




Fig. 148. — As in far-sightedness, shownig how the iens 
fails to bring- the rays of light to a focus on the retina. 

this defect and perfect vision results. Such glasses must 
we worn through the day, otherwise the headaches and 
pain in the eye caused by the astigmatism may return. 



296 PHYSIOLOGY, HYGIENE AND SANITATION 

A Cataract in the eye is a lens which no longer permits 
the rays of light to pass through undisturbed. The lens 
becomes milky white, hardened and finally becomes 
opaque, so that no light enters the eye and blindness re- 
sults. In most cases the lens can be removed by a skilled 
oculist and glasses fitted so that good vision may be ob- 
tained. 

Care of the Eyes, It is plain that the eye is the most 
delicate of the machinery of the body. Its good work de- 
pends largely upon good health and proper care. 

The eye should be examined for defects, if upon read- 
ing, sewing or using them constantly for an hour or two, 




Fig-. 149.— How a properly fitted glass or lens may cor- 
rect the condition of far-sightdeness. 

a headache or pain in the eyes is felt. If a book is held 
too close or too far away from the eye by a person, he 
should have the eyes tested for near or farsightedness 
and properly fitted glasses should be worn. 

Many so-called dull pupils in school are not really dull 
but have a defect in the eyes which causes them to see 
poorly. The right kind of glasses relieves such condi- 
tions at once. When reading or working at a task which 
requires constant use of the eyes, care should be taken 
to have the light fall over the shoulder and not let it 
shine directly into the eyes. 



SEEING 



297 



Eye Strain is the result of too long continued use of 
the eyes, or their use in a poor light, or while facing too 
strong light. Reading on a train or in an automobile is 
injurious because the 
motion of the car causes 
varying distances be- 
tween the objects and 
the eye, and the delicate 
muscles of the lens are 
constantly at work and 
on a strain to keep the 
images properly 
focused. 

When a long period 
is needed for work with 
the eyes, it is wise to 
rest for a few minutes 
so the muscles of the 
eye may relax and be 
ready to resume work 
with less fatigue. Read- 
ing while lying down is 
injurious because too 
much blood flows to the head and the eyes become red- 
dened and eye strain with headache frequently results. 

Cross Eyes are sometimes due to a defect causing near- 
sight or farsight in one eye or the other. In such cases 
glasses fitted early may cause the eyes to become straight. 
In some cases it may become necessary to have a surgeon 
operate upon the eye so that the muscles may pull the 
eye to its proper position. 




Fig-. 150.— Testing- the eye for defects 
by reading- letters twenty feet dis- 
tant. 



298 PHYSIOLOGY, HYGIENE AND SANITATION 

Summary 

The loss of the sense of sight is so terrible that great 
care should be used to protect its organs, the eyes, from 
injury. 

The eyelids with their hairs and the tears protect the 
eyeball from foreign bodies. 

The eye is almost a sphere and moves freely by the 
action of its six muscles in its bed of fat, muscles, and 
connective tissue. The cornea is the transparent window 
in front through which the iris and its opening, the pupil, 
may be seen. 

The lens is transparent, and is so arranged that by the 
action of its controlling muscles, it may change its shape 
to bring the rays of light to a focus on the retina or nerve 
of sight in the back of the eyeball. The chamber back 
of the lens is filled with vitreous humor. 

Sight is a sensation perceived in the brain when its cells 
are stimulated by impulses coming through the optic 
nerve from its end in the retina which has been stimu- 
lated by focused rays of light. 

Near and farsightedness are caused by defects in the 
eye which prevent the lens from bringing rays of light 
to a focus on the retina. The condition can be relieved 
by wearing properly fitted glasses. 

Astigmatism is caused by a defect in the cornea and 
it may be relieved by glass lenses. 

A cataract is a lens which has become more or less 
opaque and may cause blindness. When it is removed 
by a surgeon and glasses are fitted to the eye, sight is 
usually restored. 

Defects of the eye are frequent and cause eye strain, 
headaches, nervousness, and many other distressing con- 
ditions. 



SEEING 299 

The eye should be examined when trouble is suspected 
and defects corrected. 

Using the eyes too long at a time or in poor light or 
while facing a light or lying down or while reading in a 
moving car may result in eye strain. 

Questions 

1. "Why is the loss of sight so terrible? 

2. What are the organs of sight? 

3. What are the functions of the eyelids? What are 
tears? What is their purpose? How are tears formed? 

4. What is the shape of the eye? How is it protected 
from severe injuries? What tissues surround the eye? 

5. How many muscles supply the eyeball for its move- 
ment? How are they arranged? 

6. What is the cornea? What is its function? What 
is the "white" of the eye? 

7. Where is the aqueous humor? What is its color? 

8. Where is the lens of the eye? What is its function? 
What is meant by bringing rays of light to a focus 1 ! 
Illustrate this. 

9. Is the lens the same shape in your eye while you are 
reading this question as it will be if you look at the far 
end of the room? Why? What change is made in the 
shape of the lens when objects farther away are seen? 

10. What fills the back part of the eyeball? 

11. Where is the optic nerve? How is it arranged ir 
the eyeball? 

12. Where is ether? What is ether? What is light? 
Describe how we see. 

13. What is near-sightedness ? How may it be relieved ? 
How may one suspect near-sightedness? 



300 PHYSIOLOGY, HYGIENE AND SANITATION 

14. What is far-sightedness? How may it be relieved? 

15. What is astigmatism? Can it be relieved? How? 

16. What evil effects often follow defects in the eye? 

17. What is a "cataract?" 

18. What are danger signals of eye strain? What 
should be done if such defects are believed to be present? 

19. How should light be directed when the eyes are 
at work? Why? 

20. Name five causes of eye strain. 

21. What is the advantage of a rest period for the 
eyes? 

22. What is sometimes the cause of crossed eyes? How 
may they be straightened? 



CHAPTER XLI 

EMERGENCIES 

Injury by Violence. The body is often injured by cut- 
ting, pointed or dull instruments, as knives, saws, nails, 
clubs and stones. These injuries may be cuts, punctures 
or bruises, and they may be slight or severe. Slight cuts 
may be treated at home. It is safe to assume that the 
common pus germs have gotten into the cut. The object 
of treatment is to remove dirt and germs from the 
wound, bring its edges together and hold it by a dress- 
ing until nature can heal the injury. 

With clean hands the skin about the cut should be 
washed clean. A bit of soft cloth or absorbent cotton 
may be wrapped around a splinter or toothpick, dipped 
in a ten per cent solution of iodine (tincture of iodine) 
and inserted into the cut to its greatest depths. The 
iodine usually will kill any bacteria in the wound. The 
edges of the cut should then be pinched together, a piece 
of clean, white cloth placed over it, and a strip of ad- 
hesive plaster placed across the cut so that the edges 
of the wound may be kept close together. Unless there 
is much pain, redness or swelling the dressing should 
remain in place four or five days. 

If inflammation develops, the dressing should be re- 
moved and the wound washed with warm, clean water 
and soap and redressed. Severe cuts or wounds which 
become painful and sore with a discharge of pus, should 
be treated by a physician. 

Punctures are usually made by a knife blade, nail or 
splinter, and may be deep or shallow. Punctured 

301 



302 PHYSIOLOGY, HYGIENE AND SANITATION 

wounds received around the barns and stables are apt 
to result in lock-jaw (tetanus). Every accidental punc- 
tured wound should be regarded as already infected by 
some kind of germ. It should be treated like cuts and 
it must be certain that the cotton soaked in the iodine, 
on the toothpick, has been pushed all the way to the 
bottom of the wound, and it is well to repeat this two 
or three times. Ordinary turpentine is often used in- 
stead of iodine, but it is not so effective. 

If such a wound is caused by stepping on a nail about 
the stable and it is deep, it is wise to consult a physician, 
who may find it necessary to cut open the wound, clean 
it and give a serum to prevent the development of lock- 
jaw (tetanus). 

Bruises may be caused by falls or blows. The skin 
may not be cut, but the tissues beneath and even a bone 
may be severely damaged. If a bone is broken, it should 
be treated by a physician. The pain of bruises may be 
relieved by the application of several layers of woolen 
cloths wrung out of hot water. They should be changed 
frequently. The injured part should be kept at rest. 
Rubbing the part with camphor (spirits) or some other 
linament often helps to relieve the soreness. 

Bites of Animals and Swings of Insects. Dog bites are 
frequent and may result in a cut or punctured wound or 
a bruise. These wounds should be treated as already de- 
scribed. If the dog which inflicts such a wound is "mad M 
(suffering w T ith a disease, hydrophobia or rabies) the per- 
son bitten is in grave danger of contracting the disease. 

Unless it is known at once that the dog is "mad," 
it should be confined for about two weeks and watched. 
If it act peculiarly, froths at the mouth, has a fit of 
trembling when water is offered it, or bites savagely at 



EMERGENCIES 303 

objects around it, the dog is most surely a victim of 
rabies. It should at once be killed without injury to 
its brain. The brain should be sent to a laboratory, 
where certain kind of "bodies" will be found, if the dis- 
ease is present. 

If the dog has been killed at once after biting a per- 
son, its brain should be examined for the "bodies" 
(negri). A person bitten by a rabid dog or other ani- 
mal should at once take the Pasteur Treatment. This 
takes about twenty-one days and is practically certain to 
prevent the disease, with no bad results when it is prop- 
erly given. 

The so-called "mad-stones," which many people im- 
agine are of value in ' i sucking ' ' the poison from such 
wounds, are of no value, and their use may prevent the 
victim from taking the Pasteur Treatment. 

Certain insects, as honey and bumble bees, wasps, 
hornets and "yellow jackets" often sting a person in 
defense of their nests or life. The acid in the sting is 
very painful but not dangerous unless a large number 
of such insects make the attack at one time. An appli- 
cation of common cooking soda and cloths wrung out 
of cold water help to relieve the pain. 

Burns and Cold A burn may be caused by an open 
flame, a hot surface, a chemical or by electricity. In any 
case, the skin may be reddened or "blistered" or entirely 
destroyed. In burns with reddening of the skin and un- 
broken "blisters," cloths wrung out of cold water in 
which cooking soda is dissolved help relieve the burning 
pain. If the air can be kept from the burned spots, the 
pain is much less, and several folds of woolen cloth 
wrapped about the part gives relief for this reason. 

If a burn has destroyed the outer layers of skin and 



304 PHYSIOLOGY, HYGIENE AND SANITATION 

the "raw" surface is exposed, the burned spot should 
be covered with an oil of some kind. Pure vaseline ap- 
plied thick is of value. Equal parts of lime water and 
linseed oil make a good oil dressing. A soft piece of 
clean gauze or cloth of several layers is laid over the 
burn and this mixture is poured over it. Several layers 
of cloth are then applied to help exclude the air. These 
dressings should be changed every day. 

A severe burn or simple burn of large size should 
always be treated under the direction of a physician. 

Cold often injures the skin or deeper tissues, depend- 
ing upon the degree of cold and the length of time the 
body has been exposed. 

Frost Bites of the ears, nose and toes are common. 
The skin at first looks "whitish" and pain may not be 
noticed until one has been in a warm room for some 
time; then it is severe. 

The parts should be rubbed with cold water or even 
snow, and gradually brought near the fire. The skin 
capillaries may be destroyed if heat is directly applied to 
a frozen part of the body. 

A severely frozen part of the body, as the hands or 
feet, should be treated by a physician, and the parts 
kept from the heat until he arrives. 

Electric Currents may produce burns which should 
be treated as other burns. In cities where electricity 
is carried by wires or cables, one may be "shocked" 
by coming in contact with such a "live" wire. If there 
is enough current the victim may be unconscious and 
the wire may still be in contact with the body. If the 
wire is not properly removed the current may enter the 
body of the rescuer. Such wires can be safely handled 
with good rubber gloves or folded silk of sufficient thick- 



EMERGENCIES 305 

ness. The victim should be removed to a warm, dry 
room and should receive the attention of a physician 
at once. 

Sunstroke occurs usually in the hot summer months 
as a result of the intense heat of the sun. Firemen of 
great boilers and workers about fiery furnaces of found- 
ries may have a similar condition at any time. The vic- 
tim falls in a faint. The skin is burning hot and the 
heart beats rapidly. He should be removed to a cool 
spot, the clothing loosened and given plenty of fresh 
air. The heat of the body must be reduced at once and 
cold water should be poured over the victim and the 
hands and face bathed in cold water. In a little while 
he may revive and he should be kept in bed for a few 
days. 

To prevent sunstroke, light, cool clothing and hat 
should be worn. Upon feeling dizzy, hot or fainty or 
a severe headache, one should at once seek a cool place 
and rest for a while. 

Heat Prostration is also caused by intense heat. In 
this condition the body is not intensely hot and the face 
flushed. The victim is weak and almost exhausted. The 
heat of the body is low, and the patient will be pale and 
faint. He should be removed to a cool spot, laid upon the 
back, and the hands and feet rubbed until the blood cir- 
culates freely. The face and head should be bathed with 
warm water and when able, the victim should drink hot 
tea, coffee or milk. Heat prostration may be prevented in 
the same way as sunstroke. 

Summary 

Injuries by violence comprise cuts, punctures, bruises 
and may be inflicted by sharp, pointed, or dull instru- 



306 PHYSIOLOGY, HYGIENE AND SANITATION 

ments. The object of treatments is to free the wounded 
parts from infection, restore and keep them at rest until 
they may be healed. 

Tetanus or lock-jaw may follow wounds that exclude 
the air. A serum may be given to prevent it. 

Rabies is a dangerous disease that may follow the bite 
of an animal so afflicted. Its brain should be examined 
in a laboratory and if negri bodies are found, the 
Pasteur Treatment, which requires about twenty-one 
days, should be given to the victim. 

Burns and cold may destroy the skin and deeper 
tissues. Simple burns should be treated by applying a 
soothing dressing and excluding the air. Frost bites 
and freezing of the body require careful attention to 
keep the frozen body cells from dying. 

Electric currents may produce burns which are treated 
as ordinary ones. 

Intense heat may cause "sunstroke" or heat prostra- 
tion. The former is treated by cooling the blood quickly; 
the latter by applying stimulation to revive a faint and 
weakened body. ' 

Questions 

1. How may the body be injured by violence? What 
three kinds of injuries are most common? 

2. What three objects are there in treating cuts? 

3. Describe how you would treat a cut across the arm. 
Why should the hands of the person who dresses the 
wound be clean? What is the reason for using iodine? 
How should it be used? What is the purpose of putting 
adhesive plaster across the line of the cut? How long 
should such a dressing remain on the wound? What 
would lead you to change it? When would you send 
for a physician to treat a cut? 



EMERGENCIES 307 

4. What are "punctured" wounds? How would you 
treat a punctured wound made by stepping on a nail? 
What special danger may there be in punctured wounds? 

5. How may tetanus (lock-jaw) be prevented? 

6. How should bruises be treated? 

7. How should the wounds caused by the bite of dogs 
or other animals be treated? What is the danger after 
being bitten by an animal? What is hydrophobia? 
Rabies? What signs in an animal would lead you to 
think it was "mad?" What is the final proof that an 
animal has rabies? 

8. What is the prevention for rabies? How long does 
it take to complete it? 

9. What are "mad-stones?" Are they of any value? 

10. How would you treat the sting of insects? Name 
five insects that sting. 

11. How may burns be caused? What are the three 
extents of a burn? What are the objects in treat- 
ing a burn? How should a burn be treated if the skin 
has been burned off? 

12. How may cold injure the body? What are frost 
bites? How should frost bites be treated? What would 
you do if you found a person with frozen hands or feet? 

13. How should burns caused by electric currents be 
treated? What effect may heavy charges of electricity 
have on the body? How may "live" wires carrying a 
heavy charge of electricity be handled without danger? 

14. What is the cause of sunstroke? How does it 
affect a victim? What would you do if you saw a per- 
son have a sunstroke? How could you tell it was a sun- 
stroke and not a heat prostration? 

15. How would you treat a person who was suffering 
from heat prostration? 



CHAPTER XLII 

EMERGENCIES (Continued) 

Fainting is somewhat alarming, but is seldom danger- 
ous. A person about to faint becomes very pale,' weak 
and dizzy and suddenly falls unconscious. The blood 
rushes away from the brain centers and accumulates iiq. 
the large blood vessels of the body. 

The treatment of fainting consists in bringing blood 
quickly back to the brain. The person may be laid flat 
on the floor, the clothing loosened, the arms and feet 
rubbed vigorously, and cold water sprinkled on the face. 
The quickest way to revive such a person is to turn the 
body so that the head and shoulders are lower than the 
rest of the body. The simplest way to do this is to set 
the patient in an ordinary chair and tilt it backwards 
until the back of the chair and head of the patient are 
on the floor and the feet and limbs are then on a higher 
level than the rest of the body. In this position, blood 
quickly rushes to the head and the patient soon revives. 

Fits is a name applied to a condition of a person who 
at intervals becomes unconscious, with convulsions or 
jerking of the muscles of the body. Such a person is 
said to have epilepsy, and he is in danger of injuring 
himself by falling. 

It is alarming but death rarely results unless it is 
by injury from falling. 

The victim should be given plenty of fresh air and 
prevented from injuring himself by the convulsive move- 
ments of the muscles. The tongue often gets between the 
jaws and may be severely chewed unless a tightly 

308 



EMERGENCIES 309 

folded handkerchief, cork, rubber or some similar object 
is inserted between the teeth. 

Asphyxiation may result from breathing natural or 
illuminating gas, carbon-dioxide in a well or cellar, or 
by -accident in which the supply of air is used up, or by 
drowning. 

In any event, the victim is unconscious, the skin cold, 
the body limp; no breathing can be seen and the heart's 
beat can hardly be felt. 

The only way to save the life of such a person is to 
try to make him breathe again. 

This is done by artificial respiration. The best method 
of doing this is to lay the patient flat on the floor or 
ground, on his chest and stomach, face downward. The 
head should be turned to one side. The person who is 
going to do the work kneels astride the victim at the 
hips and places the hands, palm downwards, across the 
small of the victim's back and lets the fingers extend 
around the lower ribs, with the thumbs almost together. 

The operator now swings his bod}' forward and with 
his weight presses downward on the lower part of the 
chest, which forces the air, gas or water out of the 
victim's lungs. He then swings his body backward, 
keeping his hands on the back, and the air rushes into 
the lungs of the victim. This operation should be re- 
peated about eighteen times every minute at regular 
intervals, and it should be continued for two or three 
hours or as long as there is the least sign of life. After 
drowning, when death seemed certain, life has been 
saved after four hours of such work of artificial respira- 
tion. 

The victim's hands, legs and body should be vigor- 
ously rubbed, and the body kept dry and warm. 



310 PHYSIOLOGY, HYGIENE AND SANITATION 

Poisons are of many kinds but, fortunately, the prin- 
ciples of treatment, until the doctor comes, are few. 

The first things to do are : To call a doctor ; to get the 
poison out of the victim's stomach in the quickest time; 
to give something which will "kill" or make harmless 
the poison in the stomach ; to fill the stomach with some- 
thing to keep the tissues of the stomach and bowels from 
being destroyed by the action of the poison, and to keep 
up the patient's strength until the effects of the poison 
have passed away. 

An emetic is a drug or substance which will cause the 
stomach to force its contents out of the mouth, by vomit- 
ing. Sometimes a stomach pump is used for this purpose. 

A purgative is a drug or substance which will cause 
the stomach and bowels to move the waste materials 
through the body. 

An acid, when swallowed, destroys the body cells of 
the mouth, the tube to the stomach, and the walls of the 
stomach. An acid may be made almost harmless if an 
alkali can be given early enough. Vinegar, a sour acid, 
can be neutralized by adding to it common cooking soda, 
an alkali. 

•Alcohol is often taken in too large doses, so that 
stupor, "drunkenness," results. 

An emetic should be given, or the physician may use 
a stomach pump. Hot coffee, tea or milk will help re- 
store the victim. 

Acids, such as muriatic, nitric, sulphuric, if swal- 
lowed, should be neutralized by drinking a glass of lime 
water with much free lime in it, followed by the whites 
of eggs to protect the stomach wall. 

Carbolic acid poisoning is best treated by giving the 
victim alcohol, which neutralizes the effect of the acid. 
Whites of eggs are given to protect the stomach. 



EMERGENCIES 311 

Alkalis, as " concentrated' ' lye or potash, may be 
neutralized when swallowed, by giving weak vinegar. It 
should be followed by a half glass of castor oil and milk. 

Arsenic is sometimes found in rat poison or coloring 
matter of wall paper. When swallowed, the victim 
should be given warm water and mustard, a teaspoonful 
of mustard to the pint of warm water. Let the victim 
drink this until vomiting occurs. Milk and the whites of 
four or five eggs should be given. 

Bichloride of mercury poisoning should be treated 
by giving an emetic, and, at once, milk and the whites 
of eggs. 

Camphor, chloral, gasoline, lead poisoning, matches, 
morphine, strychnine and turpentine poisoning should be | 
treated by giving an emetic, and stimulants, such as hot 
coffee, tea and artificial respiration, if necessary. Iodine 
poisoning should be treated by giving an emetic, and 
starch water or flour and water mixture, and whites of 
eggs. 



CHAPTER XLIII 

COMMON DISEASES OF CHILDHOOD. 

There is a group of diseases which are spoken of as 
"catching." By this is meant that they may spread 
rapidly among persons who come in close relation with 
one sick of these diseases. 

They occur most often in childhood and young life, 
but older people often suffer from them. 

Diphtheria, scarlet fever, whooping cough, infantile 
paralysis, chicken-pox, and measles are the most com- 
mon ones and a great many young people and children 
are ill each year and many of them die from one or 
more of these diseases. 

They are spread from person to person by germs or 
seed which escape from the person who is sick, and grow 
in the bodies of others who are exposed to them. 

In all of these diseases, it is the duty of the family to 
try to keep the disease from spreading. This may be 
done by allowing no visitors in the sick room, keeping 
the victim at home until every trace of the disease is 
gone, and using the proper care in nursing so that the 
disease germs which escape from the body are promptly 
killed. 

In treating each of these diseases the victim should be 
kept alone in a well-lighted and ventilated room prop- 
erly screened. There should be no rugs or carpets on 
the floor and all the eating and drinking utensils of the 
patient should be promptly boiled. Only one person 
should nurse the patient and the members of the fam- 
ily should not be permitted in the sick room. 

312 



COMMON DISEASES OF CHILDHOOD 313 

At the close of the illness, when all danger of infec- 
tion is over, the bed-clothing should be boiled or disin- 
fected. The floors and woodwork and doorknobs should 
be scrubbed in a strong solution of lye or a bicloride 
solution made by dissolving 60 grains of bicloride of 
mercury in a gallon of water. Both of these solutions 
are poisonous and should be carefully guarded to pre- 
vent some one from accidentally swallowing them. The 
walls of the room should be rubbed with a cloth or a 
broom, which is moist with the bicloride solution. 

Diphtheria is one of the common infectious diseases 
of early life and childhood. It is a germ disease and 
develops in the nose, in the back of the throat, or ton- 
sils and in the larynx. Diphtheria of the larynx is also 
known as "membranous croup. " 

The patient has fever and a rapid pulse; the throat 
is usually "sore" and a whitish membrane grows at 
the site of the disease. 

If seen early, a large dose or two of antitoxin (5,000 
to 10,000 units) will usually cure the disease. The 
longer the disease is permitted to continue before anti- 
toxin is given, the greater danger there is of death. 

Antitoxin is harmless and its only danger is in not 
being used early, often enough or in large enough doses. 
A small dose (1,000 units) given to every other member 
of the family will usually prevent it from developing in 
them. One attack usually makes one immune from it 
afterwards. After exposure to diphtheria, the disease 
may develop in another person in about five days. The 
discharges from the nose and throat contain millions of 
the seed of the disease and they should be caught on 
cloths wet with carbolic acid solution (2 tablespoonfuls 
to a pint of water) and promptly burned. 



314 PHYSIOLOGY, HYGIENE AND SANITATION 

Scarlet Fever is a serious disease which causes high 
fever and sore throat, followed by a "breaking out" of 
the skin. The skin looks red and flushed and the erup- 
tion of "rash" appears about the second day of the 
disease. The discharges from the nose and throat con- 
tain the infection and they should be collected and de- 
stroyed as in case of diphtheria. The patient should 
be carefully protected from cold and "drafts," for the 
great danger from this disease lies in the after-effects 
on the kidneys and middle ear. 

About three to five days are necessary for a new case 
to develop after one is exposed to scarlet fever. One 
attack usually produces an immunity against other at- 
tacks. 

Whooping Cough is a serious disease occurring most 
often in children. It runs a course of several weeks, 
and is known by its peculiar cough, which sometimes 
leaves the victim almost out of breath and ends with a 
loud "whoop" which when once heard is never forgotten. 

The infection is spread from the nose and throat, and 
all materials escaping from the nose and mouth should 
be at once destroyed as in diphtheria and scarlet fever. 
This disease appears in about twenty-one days after one 
is exposed to a person having it, and an attack usually 
confers immunity for life. 

Infantile Paralysis may occur in adults as well as 
children. It comes on suddenly with fever and a sick 
stomach, and in about three days a leg, arm, foot, hand 
or the back becomes paralyzed, and the victim is un- 
able to move that part of the body. In a few cases the 
heart or lungs may be paralyzed, and death results. 

The rule for isolation and disinfection should be en- 
forced to prevent its spread. The infection is spread 



COMMON DISEASES OF CHILDHOOD 315 

from the discharges from the patient's nose and throat 
and possibly the bowels. 

Chicken Pox is a mild disease which results in a 
"breaking out" on the skin. At first they are red spots, 
but later they become like blisters and a yellow "mat- 
ter" forms under the blisters. These pustules soon dry 
up and a hard crust (a "scab") is formed. In a few days 
these fall off and they seldom leave a scar. The infection 
is in the matter in the pustules and the patient 's clothing 
and bedding should be promptly boiled or otherwise dis- 
infected. 

Measles is a common disease occurring usually in chil- 
dren. There are fever, a rapid pulse, a reddening of the 
eyes, a dry cough followed by a rash of tiny red spots 
over the body. The rash may first be seen on the "roof" 
of the mouth or sides of the cheeks. The infectious ma- 
terial is from the nose and throat and it should be care- 
fully handled as in diphtheria. 

The danger from measles lies in its after effects of 
pneumonia or ear trouble. The disease appears about 
seven days after exposure to one who is ill of it. One 
attack usually confers immunity. 

Disinfection means the employment of certain means 
to kill germs of disease. Most germs are killed when 
they become thoroughly dry, but the germs of tubercu- 
losis and lock-jaw (tetanus) may continue to live after 
prolonged drying. 

Sunlight is one of the best germicides (agents which 
will kill germs), because it thoroughly dries them and 
it destroys their structure. Bed clothing, rugs, and gar- 
ments used during illness should be thoroughly sunned 
for days before they are again used. 

Heat either by boiling or baking is one of the best 



316 PHYSIOLOGY, HYGIENE AND SANITATION 

means to kill germs. Boiling for fifteen minutes will 
kill any germ, and clothing, eating and drinking uten- 
sils and any other infected object which can be so 
treated are best disinfected in this way. 

Chemicals are often used to kill germs. It must be 
remembered that they are poisons and great care must 
be taken to keep them from getting into food or drink 
or from being accidently swallowed. Bichloride of 
mercury (60 grains to a gallon of water) is a good germ- 
icide to scrub the floors and woodwork of a sick room 
and to wipe down its walls. The hands may be washed 
in this solution and at once be rinsed in fresh water to 
free them from poison. 

Carbolic Acid in a solution of 14 of a pint to a gallon 
of water is a good agent to use for soaking bedding, 
wiping walls and woodwork of a sick room, and for 
moistening cloths for receiving discharges from the nose, 
throat and lungs. Such cloths should be burned after 
using:. 

Fresh Chloride of Lime, made by using two ounces to 
a gallon of water, is one of the best germicides and is 
probably the best for disinfecting the body wastes of a 
person ill of typhoid fever, dysentery (flux) and the 
summer complaint of children. 

Gases from the burning of sulphur, and boiling a solu- 
tion of formaldehyde are often of value in fumigating 
a room following disease. Such a procedure is val- 
uable only when all the cracks in the room are sealed up 
with paper or adhesive plaster and windows and doors 
fit tightly. The room should remain closed and sealed 
for twenty-four hours, and all drawers, closets and ward- 
robes be opened so the gas can reach their recesses. 

A pound of sulphur may be placed in a large tin pan 



COMMON DISEASES OF CHILDHOOD 317 

which is placed on bricks inside of a larger kettle with 
water in it. Alcohol may be poured over the sulphur 
and set on fire. The sulphur in burning gives off a gas 
which unites with watery vapor and forms a powerful 
germicidial gas. 

A pint of formaldehyde, as bought at drug stores, 
may be placed in a vessel over a coal oil or alcohol stove 
in a room to be disinfected. When the solution boils the 
formaldehyde gas is given off in the room and under 
proper conditions will kill most germs in twenty-four 
hours. Gases should not be used alone. The scrubbing 
of floors, woodwork and walls are of much more value. 



CHAPTER XLIV 

SANITATION 

In the preceding chapters it has been learned that cer- 
tain rules must be observed if the body is kept well and 
free from many kinds of sickness. There was also shown 
the need of carefully disposing of the infectious body 
wastes from sick people in order to limit the spread of 
disease. 

"An ounce of prevention is worth a pound of cure" is 
an old proverb which applies to many diseases. Such a 
study of the prevention of disease and the means to accom- 
plish it is embraced in the subject of sanitation. 

Sanitation of the Home. A dwelling house should be 
built high enough from the ground to be kept dry. In 
sparsely settled communities it is best to build it upon a 
rise of the ground so there is good drainage of surface 
water away from the house. 

The windows and doors should be screened from flies 
and mosquitoes, and the rooms should be large, well ven- 
tilated and lighted. 

If possible, a supply of water should be furnished from 
the city mains, or from an overhead tank from which water 
may be run through pipes, at least, to the bath room and 
kitchen. If no sewerage system is at hand, a septjic tank 
may be built in the backyard and all waste .water and 
materials can be run from the house into it. 

A septic tank can be built of concrete and is nothing 
more than a water-tight tank. A hole about five feet long, 
three feet wide and four feet deep is dug in the ground, 
and concrete poured into it until a level bottom, five inches 
thick, is made. After this hardens, planks may be set on 

318 



SANITATION 319 

end all around the hole, four inches from the dirt walls 
and this space filled with concrete and tamped tight. 
When this hardens, after two or three days, the planks may 
be removed and placed across the top, leaving about three 
inches of the top of the walls bare. Concrete may then be 
poured across the top four inches thick, leaving one end of 
the tank open for about one foot across one end. If no 
house is built over the tank, this hole may be tightly 
closed and the tank covered with a foot of earth to pre- 
vent freezing. A tile pipe may be run into this tank at 
one end to carry waste materials from the house. At the 
other end of the tank, tile may be run from it about a 
foot from the top, under the garden or yard. The oxygen 
of the air will disinfect the overflow from the tank, 

If no water is furnished in the house for the bath tub 
and toilet, a screened house may be built over the tank, 
using the top of the tank for the floor of the house. Such 
an outhouse should be so arranged that flies or rats cannot 
carry foul material into the house, and it should be kept 
clean. 

The tank must be water-tight so that drainage from it 
may not seep into the cistern, well or spring. 

If every home and public building were supplied either 
with such a septic tank or connected with a good sewerage 
system, such diseases as typhoid fever, dysentery and 
hookworm diseases would largely disappear. 

Concrete may be made by mixing one part Portland 
cement, two parts fine sand and four parts of coarser 
gravel or finely crushed rock with plenty of water. When 
ready for use, the mixture should flow like molasses. Too 
little water will cause a leaky tank. 

Garbage is a term applied to waste and refuse from the 



320 PHYSIOLOGY, HYGIENE AND SANITATION 

kitchen. Such materials in a well governed city are placed 
in large garbage cans and hauled away by the city. 

In smaller towns and in out-of-town homes, much of it 
is fed to hogs and chickens. When fed to animals it 
should be carried away from the house so that the odors of 
its decomposition may not be detected, and fed on the 
slope of a hill draining away from the source of water 
supply. 

The waste water from the kitchen may be run into a 
septic tank. If not fed to animals, the solid or "dry" 




Fig - . 151.— A filthy, unsanitary backyard. A breeding- 
place for disease just across the alley from a sani- 
tary home. Showing why health laws should be 
enforced. 



garbage should either be burned or buried in a trench 
which will not drain toward the water supply. 

The premises about a home should be kept free from 
weeds which may harbor mosquitoes, empty tin cans, and 
uncovered rain barrels which offer a place for mosquitoes 
to hatch. "Wriggle-tails" are young mosquitoes in the 



SANITATION 



321 



first stage of their life after hatching from the eggs. They 
may be killed by pouring crude oil on the water. 

The back porch and yards should be kept free from rub- 
bish and kept clean and orderly. Remember that filth 
breeds disease. 

Sanitation of the Community. Unfortunately, many 
people either do not know how to prevent the spread of 
diseases, or they are too careless or indifferent to do so. 
One may live in a home which is kept sanitary, but be ex- 



j 

1 


1 l ••• 










ill 






9&JL ft 1 


^^W*' 'SL' '^3&* j 





Fig-. 152.— Boy scouts in a clean-up campaign for 
community sanitation. 

posed to the drainage, flies, rats and dangers of a neigh- 
bor's house and premises which are ill-kept and breeding 
places for disease. 

It is not right for any person wilfully to permit the so- 
called " catching" or communicable diseases to spread, and 
health laws with penalties are necessary to compel indif- 
ferent or ignorant people to protect their own and other 
people's health and lives. 



322 PHYSIOLOGY, HYGIENE AND SANITATION 

Health Boards. In larger cities, there is usually a com- 
mittee of citizens whose duty it is to enforce the health 
laws. They usually operate through a health officer, whose 
duty it is to see that health laws relating to them are en- 
forced ; that sanitary inspections are made of schools, homes 
and public buildings, dairies, water supplies, food factor- 
ies and markets. 

There, also, is usually a county board of health and a 
county health officer, whose duty is to enforce the health 
laws and rules in an entire county. 




Fig-. 153.— College girls in a health parade for a 
clean-up campaign, conducted by the visiting nurse 
of a County Health and Welfare League. 



The State Board of Health is one of the most important 
departments of the State, for through it, health laws for 
the entire state are enforced. It is usually able to make 
free examinations of water, body wastes and discharges 
from sick people; to help locate diseases and tell of their 
nature and danger; to make sanitary inspections; to keep 



SANITATION 323 

records of births and deaths and direct the health work of 
the counties. 

It is the duty of every good citizen to uphold the efforts 
of health officials and to insist upon the passage of laws 
with ample funds for their operation. 

Volunteer Organizations. Many cities and counties 
organize Anti-Tuberculosis Societies, City and County 
Health and Welfare Leagues for the purpose of nursing 
the sick and helping them to prevent sickness. Many of 
them employ one or more visiting nurses, who give nursing 
care to those unable to employ a nurse, and instruct the 
people in disease prevention ; they visit schools and instruct 
pupils in hygiene and examine them for defective eyes, 
teeth and hearing and for adenoids and tonsils. 

The visiting nurse encourages victims of tuberculosis by 
showing them how to get well and live in safety with the 
family, and persuades many to go to a tuberculosis sani- 
torium for treatment and instruction in the management 
of their disease. 

Many schools organize Junior Health and Welfare 
Leagues, and elect one of the pupils as school health offi- 
cer. The school board of health is composed of a few 
pupils and it is their duty to see that the rules for ventila- 
tion and cleanliness of the school room are enforced; that 
the common drinking cup is not used; the necessary out- 
houses are kept clean and in a sanitary condition ; that 
spitting upon the floors is not permitted and to enforce 
the rules against sneezing and coughing with the nose and 
mouth uncovered. 

The members of the school health board and the health 
officer are changed from time to time and offenders against 
the health laws of the school are required by the teacher 
to perform some task that will be in keeping with the 



324 PHYSIOLOGY, HYGIENE AND SANITATION 

offense committed. Often the offender against the rules 
may be tried by a jury of pupils and the teacher explains 
the offense and why it should not have been committed, 
and the reason for inflicting a penalty. 

The Modern Health Crusader Movement in schools pro- 
vides a series of promotions and prizes for pupils who 
will for a number of w r eeks perform ten health tasks each 
day. 

Tuberculosis Sanatoriums have been built by many 
states to provide for the instruction and treatment of 
this disease. 

The cost to the state is small compared to the loss in life 
and health of its citizens. 

Such institutions have been erected by many counties, 
fraternal organizations and volunteer organizations. 

The average time a consumptive should remain in a 
sanatorium for the disease to be arrested or cured is about 
six months. After such a treatment a patient has learned 
so well to protect himself and others that he may live in 
safety with his family and friends. 




OONTRAOT EDITION 



RETAIL PRSCE, 82 CENTS 
EXCHANGE PftSCE, 48 CENTS 

The prices printed hereon are fixed by State contract, an>5 
any higher prices are unlawful ; any deviation therefrom should 
be reported to your County Superintendent, or to the State Text 
Book Commission at Frankfort 



